Termux: "Installing build dependencies ... error"

[maxigaz]

When I try to install buku in Termux through pip install buku. I get a build error.

I've found in #291 that urllib3 is required as a dependency, so I ran pip install urllib3 just in case. The building process still fails.

Here's the terminal output (with urllib3 installed):

$ pip install buku
Collecting buku
  Using cached https://files.pythonhosted.org/packages/4e/51/d736d9ef4ee56bdd576aefdeded6eee5ccc60f3e07467836d4585b8783c7/buku-4.2.2.tar.gz
Collecting beautifulsoup4>=4.4.1 (from buku)
  Using cached https://files.pythonhosted.org/packages/1d/5d/3260694a59df0ec52f8b4883f5d23b130bc237602a1411fa670eae12351e/beautifulsoup4-4.7.1-py3-none-any.whl
Collecting certifi (from buku)
  Using cached https://files.pythonhosted.org/packages/60/75/f692a584e85b7eaba0e03827b3d51f45f571c2e793dd731e598828d380aa/certifi-2019.3.9-py2.py3-none-any.whl
Collecting cryptography>=1.2.3 (from buku)
  Using cached https://files.pythonhosted.org/packages/c2/95/f43d02315f4ec074219c6e3124a87eba1d2d12196c2767fadfdc07a83884/cryptography-2.7.tar.gz
  Installing build dependencies ... error
  ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip install --ignore-installed --no-user --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-5cjll9_t/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'setuptools>=40.6.0' wheel 'cffi>=1.8,!=1.11.3; python_implementation != '"'"'PyPy'"'"'':
  ERROR: Collecting setuptools>=40.6.0
    Using cached https://files.pythonhosted.org/packages/ec/51/f45cea425fd5cb0b0380f5b0f048ebc1da5b417e48d304838c02d6288a1e/setuptools-41.0.1-py2.py3-none-any.whl
  Collecting wheel
    Using cached https://files.pythonhosted.org/packages/bb/10/44230dd6bf3563b8f227dbf344c908d412ad2ff48066476672f3a72e174e/wheel-0.33.4-py2.py3-none-any.whl
  Collecting cffi!=1.11.3,>=1.8
    Using cached https://files.pythonhosted.org/packages/93/1a/ab8c62b5838722f29f3daffcc8d4bd61844aa9b5f437341cc890ceee483b/cffi-1.12.3.tar.gz
  Collecting pycparser (from cffi!=1.11.3,>=1.8)
    Using cached https://files.pythonhosted.org/packages/68/9e/49196946aee219aead1290e00d1e7fdeab8567783e83e1b9ab5585e6206a/pycparser-2.19.tar.gz
  Installing collected packages: setuptools, wheel, pycparser, cffi
    Running setup.py install for pycparser: started
      Running setup.py install for pycparser: finished with status 'done'
    Running setup.py install for cffi: started
      Running setup.py install for cffi: finished with status 'error'
      ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-z0ys4ih0/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-211upxvt/install-record.txt --single-version-externally-managed --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-5cjll9_t/overlay --compile:
      ERROR: unable to execute 'arm-linux-androideabi-clang': No such file or directory
      unable to execute 'arm-linux-androideabi-clang': No such file or directory

          No working compiler found, or bogus compiler options passed to
          the compiler from Python's standard "distutils" module.  See
          the error messages above.  Likely, the problem is not related
          to CFFI but generic to the setup.py of any Python package that
          tries to compile C code.  (Hints: on OS/X 10.8, for errors about
          -mno-fused-madd see http://stackoverflow.com/questions/22313407/
          Otherwise, see https://wiki.python.org/moin/CompLangPython or
          the IRC channel #python on irc.freenode.net.)

          Trying to continue anyway.  If you are trying to install CFFI from
          a build done in a different context, you can ignore this warning.

      running install
      running build
      running build_py
      creating build
      creating build/lib.linux-armv7l-3.7
      creating build/lib.linux-armv7l-3.7/cffi
      copying cffi/vengine_cpy.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/model.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/commontypes.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/error.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/backend_ctypes.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/cparser.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/ffiplatform.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/pkgconfig.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/vengine_gen.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/api.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/lock.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/__init__.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/setuptools_ext.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/cffi_opcode.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/verifier.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/recompiler.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_cffi_include.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/parse_c_type.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_embedding.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_cffi_errors.h -> build/lib.linux-armv7l-3.7/cffi
      running build_ext
      building '_cffi_backend' extension
      creating build/temp.linux-armv7l-3.7
      creating build/temp.linux-armv7l-3.7/c
      arm-linux-androideabi-clang -mfloat-abi=softfp -mfpu=vfpv3-d16 -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -fPIC -I/usr/include/ffi -I/usr/include/libffi -I/data/data/com.termux/files/usr/include/python3.7m -c c/_cffi_backend.c -o build/temp.linux-armv7l-3.7/c/_cffi_backend.o
      unable to execute 'arm-linux-androideabi-clang': No such file or directory
      error: command 'arm-linux-androideabi-clang' failed with exit status 1
      ----------------------------------------
  ERROR: Command "/data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-z0ys4ih0/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-211upxvt/install-record.txt --single-version-externally-managed --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-5cjll9_t/overlay --compile" failed with error code 1 in /data/data/com.termux/files/usr/tmp/pip-install-z0ys4ih0/cffi/
  ----------------------------------------
ERROR: Command "/data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip install --ignore-installed --no-user --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-5cjll9_t/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'setuptools>=40.6.0' wheel 'cffi>=1.8

[jarun]

@rachmadaniHaryono and @fornwall any ideas?

[rachmadaniHaryono]

@maxigaz can you try pip3 install -U cffi and tell us the version number?

and also your os information? (like with neofetch)

[maxigaz]

Do you mean the version number of the available package cffi? It's 1.12.3.

Although I have a similar error message:

$ pip3 install -U cffi
Collecting cffi
  Using cached https://files.pythonhosted.org/packages/93/1a/ab8c62b5838722f29f3daffcc8d4bd61844aa9b5f437341cc890ceee483b/cffi-1.12.3.tar.gz
Collecting pycparser (from cffi)
  Using cached https://files.pythonhosted.org/packages/68/9e/49196946aee219aead1290e00d1e7fdeab8567783e83e1b9ab5585e6206a/pycparser-2.19.tar.gz
Installing collected packages: pycparser, cffi
  Running setup.py install for pycparser ... done
  Running setup.py install for cffi ... error
    ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-yzqotnrn/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-u24gqjzt/install-record.txt --single-version-externally-managed --compile:
    ERROR: unable to execute 'arm-linux-androideabi-clang': No such file or directory
    unable to execute 'arm-linux-androideabi-clang': No such file or directory

        No working compiler found, or bogus compiler options passed to
        the compiler from Python's standard "distutils" module.  See
        the error messages above.  Likely, the problem is not related
        to CFFI but generic to the setup.py of any Python package that
        tries to compile C code.  (Hints: on OS/X 10.8, for errors about
        -mno-fused-madd see http://stackoverflow.com/questions/22313407/
        Otherwise, see https://wiki.python.org/moin/CompLangPython or
        the IRC channel #python on irc.freenode.net.)

        Trying to continue anyway.  If you are trying to install CFFI from
        a build done in a different context, you can ignore this warning.

    running install
    running build
    running build_py
    creating build
    creating build/lib.linux-armv7l-3.7
    creating build/lib.linux-armv7l-3.7/cffi
    copying cffi/vengine_cpy.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/model.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/commontypes.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/error.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/backend_ctypes.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/cparser.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/ffiplatform.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/pkgconfig.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/vengine_gen.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/api.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/lock.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/__init__.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/setuptools_ext.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/cffi_opcode.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/verifier.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/recompiler.py -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/_cffi_include.h -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/parse_c_type.h -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/_embedding.h -> build/lib.linux-armv7l-3.7/cffi
    copying cffi/_cffi_errors.h -> build/lib.linux-armv7l-3.7/cffi
    running build_ext
    building '_cffi_backend' extension
    creating build/temp.linux-armv7l-3.7
    creating build/temp.linux-armv7l-3.7/c
    arm-linux-androideabi-clang -mfloat-abi=softfp -mfpu=vfpv3-d16 -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -fPIC -I/usr/include/ffi -I/usr/include/libffi -I/data/data/com.termux/files/usr/include/python3.7m -c c/_cffi_backend.c -o build/temp.linux-armv7l-3.7/c/_cffi_backend.o
    unable to execute 'arm-linux-androideabi-clang': No such file or directory
    error: command 'arm-linux-androideabi-clang' failed with exit status 1
    ----------------------------------------
ERROR: Command "/data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-yzqotnrn/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-u24gqjzt/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /data/data/com.termux/files/usr/tmp/pip-install-yzqotnrn/cffi/

Here's the system info according to neofetch (although it doesn't mention, I'm running LineageOS, by the way):

OS: Android 7.1.2 armv7l
Host: Motorola MotoG3
Kernel: 3.10.49-g415000d
Uptime: 3 hours, 43 mins
Packages: 91 (dpkg), 1 (pkg)
Shell: zsh 5.7.1
Terminal: /dev/pts/1
CPU: Qualcomm MSM8916 (4) @ 1.363GHz
Memory: 608MiB / 899MiB

[rachmadaniHaryono]

based on termux/termux-packages#2430

pkg install libcrypt-dev
pkg install libffi-dev

if this work can you document the entire process @maxigaz ?

[jarun]

@maxigaz I need a favour from you once this is through. Could you add a wiki page with the steps on Termux? I have made it editable for all.

[maxigaz]

I need a favour from you once this is through. Could you add a wiki page with the steps on Termux?

Do you mean here, on GitHub? Sure, I can do that once I got it working.

I still get an error though, even after having installed libcrypt-dev and libffi-dev.

However, I could at least get rid of the part "unable to execute 'arm-linux-androideabi-clang': No such file or directory" from the previous outputs by installing clang through pkg install clang.

$ pip install buku
Collecting buku
  Using cached https://files.pythonhosted.org/packages/4e/51/d736d9ef4ee56bdd576aefdeded6eee5ccc60f3e07467836d4585b8783c7/buku-4.2.2.tar.gz
Collecting beautifulsoup4>=4.4.1 (from buku)
  Using cached https://files.pythonhosted.org/packages/1d/5d/3260694a59df0ec52f8b4883f5d23b130bc237602a1411fa670eae12351e/beautifulsoup4-4.7.1-py3-none-any.whl
Requirement already satisfied: certifi in /data/data/com.termux/files/usr/lib/python3.7/site-packages (from buku) (2019.3.9)
Collecting cryptography>=1.2.3 (from buku)
  Using cached https://files.pythonhosted.org/packages/c2/95/f43d02315f4ec074219c6e3124a87eba1d2d12196c2767fadfdc07a83884/cryptography-2.7.tar.gz
  Installing build dependencies ... error
  ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip install --ignore-installed --no-user --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-ivi4wqcs/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'setuptools>=40.6.0' wheel 'cffi>=1.8,!=1.11.3; python_implementation != '"'"'PyPy'"'"'':
  ERROR: Collecting setuptools>=40.6.0
    Using cached https://files.pythonhosted.org/packages/ec/51/f45cea425fd5cb0b0380f5b0f048ebc1da5b417e48d304838c02d6288a1e/setuptools-41.0.1-py2.py3-none-any.whl
  Collecting wheel
    Using cached https://files.pythonhosted.org/packages/bb/10/44230dd6bf3563b8f227dbf344c908d412ad2ff48066476672f3a72e174e/wheel-0.33.4-py2.py3-none-any.whl
  Collecting cffi!=1.11.3,>=1.8
    Using cached https://files.pythonhosted.org/packages/93/1a/ab8c62b5838722f29f3daffcc8d4bd61844aa9b5f437341cc890ceee483b/cffi-1.12.3.tar.gz
  Collecting pycparser (from cffi!=1.11.3,>=1.8)
    Using cached https://files.pythonhosted.org/packages/68/9e/49196946aee219aead1290e00d1e7fdeab8567783e83e1b9ab5585e6206a/pycparser-2.19.tar.gz
  Installing collected packages: setuptools, wheel, pycparser, cffi
    Running setup.py install for pycparser: started
      Running setup.py install for pycparser: finished with status 'done'
    Running setup.py install for cffi: started
      Running setup.py install for cffi: finished with status 'error'
      ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-4s46wsow/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-foh2k1ab/install-record.txt --single-version-externally-managed --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-ivi4wqcs/overlay --compile:
      ERROR: running install
      running build
      running build_py
      creating build
      creating build/lib.linux-armv7l-3.7
      creating build/lib.linux-armv7l-3.7/cffi
      copying cffi/vengine_cpy.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/model.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/commontypes.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/error.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/backend_ctypes.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/cparser.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/ffiplatform.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/pkgconfig.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/vengine_gen.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/api.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/lock.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/__init__.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/setuptools_ext.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/cffi_opcode.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/verifier.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/recompiler.py -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_cffi_include.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/parse_c_type.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_embedding.h -> build/lib.linux-armv7l-3.7/cffi
      copying cffi/_cffi_errors.h -> build/lib.linux-armv7l-3.7/cffi
      running build_ext
      building '_cffi_backend' extension
      creating build/temp.linux-armv7l-3.7
      creating build/temp.linux-armv7l-3.7/c
      arm-linux-androideabi-clang -mfloat-abi=softfp -mfpu=vfpv3-d16 -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -fPIC -DUSE__THREAD -DHAVE_SYNC_SYNCHRONIZE -I/usr/include/ffi -I/usr/include/libffi -I/data/data/com.termux/files/usr/include/python3.7m -c c/_cffi_backend.c -o build/temp.linux-armv7l-3.7/c/_cffi_backend.o
      c/_cffi_backend.c:2:10: fatal error: 'Python.h' file not found
      #include <Python.h>
               ^~~~~~~~~~
      1 error generated.
      error: command 'arm-linux-androideabi-clang' failed with exit status 1
      ----------------------------------------
  ERROR: Command "/data/data/com.termux/files/usr/bin/python -u -c 'import setuptools, tokenize;__file__='"'"'/data/data/com.termux/files/usr/tmp/pip-install-4s46wsow/cffi/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /data/data/com.termux/files/usr/tmp/pip-record-foh2k1ab/install-record.txt --single-version-externally-managed --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-ivi4wqcs/overlay --compile" failed with error code 1 in /data/data/com.termux/files/usr/tmp/pip-install-4s46wsow/cffi/
  ----------------------------------------
ERROR: Command "/data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip install --ignore-installed --no-user --prefix /data/data/com.termux/files/usr/tmp/pip-build-env-ivi4wqcs/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'setuptools>=40.6.0' wheel 'cffi>=1.8

[maxigaz]

After some searching on the issue tracker of termux-packages, coming across this issue and trial and error, I've got it!

First, I realised that I had python installed, but not python-dev. Also installing the latter took care of the build dependencies error for cryptography.

So the build process got further this time, but it still stopped at Building wheels for collected packages: cryptography:

Building wheels for collected packages: cryptography
  Building wheel for cryptography (PEP 517) ... error
  ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip/_vendor/pep517/_in_process.py build_wheel /data/data/com.termux/files/usr/tmp/tmptf8hh26f:
  ERROR: running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.linux-armv7l-3.7
  creating build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/__about__.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/__init__.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/exceptions.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/fernet.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/utils.py -> build/lib.linux-armv7l-3.7/cryptography
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat
  copying src/cryptography/hazmat/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat
  copying src/cryptography/hazmat/_oid.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat
  creating build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/base.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/certificate_transparency.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/extensions.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/general_name.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/name.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/ocsp.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/oid.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  copying src/cryptography/hazmat/backends/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  copying src/cryptography/hazmat/backends/interfaces.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings
  copying src/cryptography/hazmat/bindings/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/cmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/constant_time.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/hashes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/hmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/keywrap.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/padding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/poly1305.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/aead.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/backend.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ciphers.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/cmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/decode_asn1.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/dh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/dsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ec.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ed25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ed448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/encode_asn1.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/hashes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/hmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ocsp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/poly1305.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/rsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x509.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/_conditional.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/binding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/dh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/dsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ec.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ed25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ed448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/padding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/rsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/x25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/x448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/aead.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/algorithms.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/base.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/modes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/concatkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/hkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/kbkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/pbkdf2.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/scrypt.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/x963kdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/base.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/pkcs12.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/ssh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/hotp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/totp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  running egg_info
  writing src/cryptography.egg-info/PKG-INFO
  writing dependency_links to src/cryptography.egg-info/dependency_links.txt
  writing requirements to src/cryptography.egg-info/requires.txt
  writing top-level names to src/cryptography.egg-info/top_level.txt
  reading manifest file 'src/cryptography.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  no previously-included directories found matching 'docs/_build'
  warning: no previously-included files found matching 'vectors'
  warning: no previously-included files matching '*' found under directory 'vectors'
  warning: no previously-included files found matching 'azure-pipelines.yml'
  warning: no previously-included files found matching '.azure-pipelines'
  warning: no previously-included files found matching '.travis.yml'
  warning: no previously-included files found matching '.travis'
  warning: no previously-included files matching '*' found under directory '.azure-pipelines'
  warning: no previously-included files matching '*' found under directory '.travis'
  warning: no previously-included files found matching 'release.py'
  warning: no previously-included files found matching '.coveragerc'
  warning: no previously-included files found matching 'codecov.yml'
  warning: no previously-included files found matching 'dev-requirements.txt'
  warning: no previously-included files found matching 'rtd-requirements.txt'
  warning: no previously-included files found matching 'tox.ini'
  writing manifest file 'src/cryptography.egg-info/SOURCES.txt'
  running build_ext
  generating cffi module 'build/temp.linux-armv7l-3.7/_padding.c'
  creating build/temp.linux-armv7l-3.7
  generating cffi module 'build/temp.linux-armv7l-3.7/_constant_time.c'
  generating cffi module 'build/temp.linux-armv7l-3.7/_openssl.c'
  building '_openssl' extension
  creating build/temp.linux-armv7l-3.7/build
  creating build/temp.linux-armv7l-3.7/build/temp.linux-armv7l-3.7
  arm-linux-androideabi-clang -mfloat-abi=softfp -mfpu=vfpv3-d16 -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -fPIC -I/data/data/com.termux/files/usr/include/python3.7m -c build/temp.linux-armv7l-3.7/_openssl.c -o build/temp.linux-armv7l-3.7/build/temp.linux-armv7l-3.7/_openssl.o -Wconversion -Wno-error=sign-conversion
  build/temp.linux-armv7l-3.7/_openssl.c:498:10: fatal error: 'openssl/opensslv.h' file not found
  #include <openssl/opensslv.h>
           ^~~~~~~~~~~~~~~~~~~~
  1 error generated.
  error: command 'arm-linux-androideabi-clang' failed with exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for cryptography
  Running setup.py clean for cryptography
Failed to build cryptography
ERROR: Could not build wheels for cryptography which use PEP 517 and cannot be installed directly
 ✘ u0_a104@localhost  ~  pip3 install -U cffi                                         <<<
 ✘ u0_a104@localhost  ~  pip install cryptography
Collecting cryptography
  Using cached https://files.pythonhosted.org/packages/c2/95/f43d02315f4ec074219c6e3124a87eba1d2d12196c2767fadfdc07a83884/cryptography-2.7.tar.gz
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
    Preparing wheel metadata ... done
Collecting asn1crypto>=0.21.0 (from cryptography)
  Using cached https://files.pythonhosted.org/packages/ea/cd/35485615f45f30a510576f1a56d1e0a7ad7bd8ab5ed7cdc600ef7cd06222/asn1crypto-0.24.0-py2.py3-none-any.whl
Requirement already satisfied: six>=1.4.1 in /data/data/com.termux/files/usr/lib/python3.7/site-packages (from cryptography) (1.11.0)
Collecting cffi!=1.11.3,>=1.8 (from cryptography)
  Using cached https://files.pythonhosted.org/packages/93/1a/ab8c62b5838722f29f3daffcc8d4bd61844aa9b5f437341cc890ceee483b/cffi-1.12.3.tar.gz
Requirement already satisfied: pycparser in /data/data/com.termux/files/usr/lib/python3.7/site-packages (from cffi!=1.11.3,>=1.8->cryptography) (2.19)
Building wheels for collected packages: cryptography
  Building wheel for cryptography (PEP 517) ... error
  ERROR: Complete output from command /data/data/com.termux/files/usr/bin/python /data/data/com.termux/files/usr/lib/python3.7/site-packages/pip/_vendor/pep517/_in_process.py build_wheel /data/data/com.termux/files/usr/tmp/tmpg00l1u96:
  ERROR: running bdist_wheel
  running build
  running build_py
  creating build
  creating build/lib.linux-armv7l-3.7
  creating build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/__about__.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/__init__.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/exceptions.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/fernet.py -> build/lib.linux-armv7l-3.7/cryptography
  copying src/cryptography/utils.py -> build/lib.linux-armv7l-3.7/cryptography
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat
  copying src/cryptography/hazmat/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat
  copying src/cryptography/hazmat/_oid.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat
  creating build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/base.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/certificate_transparency.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/extensions.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/general_name.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/name.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/ocsp.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  copying src/cryptography/x509/oid.py -> build/lib.linux-armv7l-3.7/cryptography/x509
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  copying src/cryptography/hazmat/backends/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  copying src/cryptography/hazmat/backends/interfaces.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings
  copying src/cryptography/hazmat/bindings/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/cmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/constant_time.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/hashes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/hmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/keywrap.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/padding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  copying src/cryptography/hazmat/primitives/poly1305.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/aead.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/backend.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ciphers.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/cmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/decode_asn1.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/dh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/dsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ec.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ed25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ed448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/encode_asn1.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/hashes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/hmac.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/ocsp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/poly1305.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/rsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  copying src/cryptography/hazmat/backends/openssl/x509.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/backends/openssl
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/_conditional.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  copying src/cryptography/hazmat/bindings/openssl/binding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/bindings/openssl
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/dh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/dsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ec.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ed25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/ed448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/padding.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/rsa.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/x25519.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  copying src/cryptography/hazmat/primitives/asymmetric/x448.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/asymmetric
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/aead.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/algorithms.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/base.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  copying src/cryptography/hazmat/primitives/ciphers/modes.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/ciphers
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/concatkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/hkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/kbkdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/pbkdf2.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/scrypt.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  copying src/cryptography/hazmat/primitives/kdf/x963kdf.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/kdf
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/base.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/pkcs12.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  copying src/cryptography/hazmat/primitives/serialization/ssh.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/serialization
  creating build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/__init__.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/hotp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/totp.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  copying src/cryptography/hazmat/primitives/twofactor/utils.py -> build/lib.linux-armv7l-3.7/cryptography/hazmat/primitives/twofactor
  running egg_info
  writing src/cryptography.egg-info/PKG-INFO
  writing dependency_links to src/cryptography.egg-info/dependency_links.txt
  writing requirements to src/cryptography.egg-info/requires.txt
  writing top-level names to src/cryptography.egg-info/top_level.txt
  reading manifest file 'src/cryptography.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  no previously-included directories found matching 'docs/_build'
  warning: no previously-included files found matching 'vectors'
  warning: no previously-included files matching '*' found under directory 'vectors'
  warning: no previously-included files found matching 'azure-pipelines.yml'
  warning: no previously-included files found matching '.azure-pipelines'
  warning: no previously-included files found matching '.travis.yml'
  warning: no previously-included files found matching '.travis'
  warning: no previously-included files matching '*' found under directory '.azure-pipelines'
  warning: no previously-included files matching '*' found under directory '.travis'
  warning: no previously-included files found matching 'release.py'
  warning: no previously-included files found matching '.coveragerc'
  warning: no previously-included files found matching 'codecov.yml'
  warning: no previously-included files found matching 'dev-requirements.txt'
  warning: no previously-included files found matching 'rtd-requirements.txt'
  warning: no previously-included files found matching 'tox.ini'
  writing manifest file 'src/cryptography.egg-info/SOURCES.txt'
  running build_ext
  generating cffi module 'build/temp.linux-armv7l-3.7/_padding.c'
  creating build/temp.linux-armv7l-3.7
  generating cffi module 'build/temp.linux-armv7l-3.7/_constant_time.c'
  generating cffi module 'build/temp.linux-armv7l-3.7/_openssl.c'
  building '_openssl' extension
  creating build/temp.linux-armv7l-3.7/build
  creating build/temp.linux-armv7l-3.7/build/temp.linux-armv7l-3.7
  arm-linux-androideabi-clang -mfloat-abi=softfp -mfpu=vfpv3-d16 -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -march=armv7-a -mfpu=neon -mfloat-abi=softfp -mthumb -Os -fPIC -I/data/data/com.termux/files/usr/include/python3.7m -c build/temp.linux-armv7l-3.7/_openssl.c -o build/temp.linux-armv7l-3.7/build/temp.linux-armv7l-3.7/_openssl.o -Wconversion -Wno-error=sign-conversion
  build/temp.linux-armv7l-3.7/_openssl.c:498:10: fatal error: 'openssl/opensslv.h' file not found
  #include <openssl/opensslv.h>
           ^~~~~~~~~~~~~~~~~~~~
  1 error generated.
  error: command 'arm-linux-androideabi-clang' failed with exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for cryptography
  Running setup.py clean for cryptography
Failed to build cryptography
ERROR: Could not build wheels for cryptography which use PEP 517 and cannot be installed directly

The missing piece was pkg install openssl-dev. After that pip buku install finally completed successfully.

---

So, in a new wiki page, I can sum up the steps of installing the necessary packages and briefly describing which fixes what error if that's OK with you.

[maxigaz]

I've just created a wiki page here. I decided not to go into much detail about what possible errors may occur, but include a link to this issue for reference instead.

Thank you for making this awesome tool called Buku!

[jarun]

Thank you so much!