MAINT: valid doctest for config_py function show() (#17621)
MAINT: valid doctest for config_py function show() (#17621)

numpy.distutils generates a function `__config__.show`. This change
makes the docstring of that function complete (with the required
imports) and runnable. This prevents numpy.distutils from adding
doctests that will fail -- if picked-up by the test runner.
rgommers/numpy,endolith/numpy,seberg/numpy,charris/numpy,mattip/numpy,madphysicist/numpy,madphysicist/numpy,pbrod/numpy,charris/numpy,endolith/numpy,pdebuyl/numpy,endolith/numpy,jakirkham/numpy,grlee77/numpy,madphysicist/numpy,anntzer/numpy,anntzer/numpy,numpy/numpy,simongibbons/numpy,charris/numpy,grlee77/numpy,rgommers/numpy,mhvk/numpy,mattip/numpy,jakirkham/numpy,pdebuyl/numpy,pdebuyl/numpy,seberg/numpy,pbrod/numpy,endolith/numpy,mattip/numpy,numpy/numpy,numpy/numpy,seberg/numpy,jakirkham/numpy,mattip/numpy,pbrod/numpy,anntzer/numpy,simongibbons/numpy,simongibbons/numpy,simongibbons/numpy,mhvk/numpy,grlee77/numpy,madphysicist/numpy,charris/numpy,madphysicist/numpy,jakirkham/numpy,numpy/numpy,mhvk/numpy,rgommers/numpy,grlee77/numpy,pdebuyl/numpy,pbrod/numpy,grlee77/numpy,rgommers/numpy,jakirkham/numpy,mhvk/numpy,seberg/numpy,anntzer/numpy,mhvk/numpy,pbrod/numpy,simongibbons/numpy