code: def pyc_to_py(path_to_file):
      
      stem, ext = os.path.splitext(path_to_file)
      if ext == '.pyc':
          return '%s.py' % stem
      return path_to_file
docs: Change some file extensions to those which are more likely to be text
  
      >>> pyc_to_py('vim.pyc') == 'vim.py'
      True