API: accept that pyplot.get_cmap is not going away

Add it to the rendered docs.

Author: tacaswell

doc/api/next_api_changes/deprecations/23668-TC.rst

@@ -19,4 +19,4 @@ following functions have been marked for pending deprecation:
 - `matplotlib.cm.unregister_cmap` - use ``matplotlib.colormaps.unregister`` instead
 - ``matplotlib.pyplot.register_cmap`` - use ``matplotlib.colormaps.register`` instead
 
-The ``matplotlib.pyplot.get_cmap`` function will stay available for backward compatibility.
+The `matplotlib.pyplot.get_cmap` function will stay available for backward compatibility.

doc/api/pyplot_summary.rst

@@ -64,6 +64,7 @@ Plotting commands
    gcf
    gci
    get
+   get_cmap
    get_figlabels
    get_fignums
    getp

lib/matplotlib/pyplot.py

@@ -2022,7 +2022,7 @@ def get_plot_commands():
     # This works by searching for all functions in this module and removing
     # a few hard-coded exclusions, as well as all of the colormap-setting
     # functions, and anything marked as private with a preceding underscore.
-    exclude = {'colormaps', 'colors', 'get_plot_commands', 'get_cmap',
+    exclude = {'colormaps', 'colors', 'get_plot_commands',
                *_NON_PLOT_COMMANDS, *colormaps}
     this_module = inspect.getmodule(get_plot_commands)
     return sorted(
@@ -2069,6 +2069,8 @@ def clim(vmin=None, vmax=None):
     im.set_clim(vmin, vmax)
 
 
+# eventually this implementation should move here, use indirection for now to
+# avoid having two copies of the code floating around.
 def get_cmap(name=None, lut=None):
     return cm._get_cmap(name=name, lut=lut)
 get_cmap.__doc__ = cm._get_cmap.__doc__