Feature request: Add shlex_join

[Poikilos]

Maybe add something like:

if sys.version_info.major > 3 and sys.version_info.minor >= 8:
    import shlex
    shlex_join = shlex.join
    del shlex
else:
    def shlex_join(parts):
        result = ""
        sep = ""
        for part in parts:
            result += sep
            sep = " "
            result += shlex_quote(part)
        return result
    # Maybe not now but script importing it could do something like: import shlex; import six; shlex.join = six.shlex_join