  
  def find_command(cmd, path=None, pathext=None):
      if path is None:
          path = os.environ.get('PATH', '').split(os.pathsep)
      if isinstance(path, six.string_types):
          path = [path]
      # check if there are funny path extensions for executables, e.g. Windows
      if pathext is None:
          pathext = os.environ.get('PATHEXT', '.COM;.EXE;.BAT;.CMD').split(os.pathsep)
      # don't use extensions if the command ends with one of them
 
</s> remove         if not isinstance(path, six.string_types):
 </s> add         if not isinstance(path, str): </s> remove         if isinstance(format_module_path, six.string_types):
 </s> add         if isinstance(format_module_path, str): </s> remove         if isinstance(file, six.string_types) or file is None:
 </s> add         if isinstance(file, str) or file is None: </s> remove         self.assertIsInstance(resolved_url, six.text_type)
 </s> add         self.assertIsInstance(resolved_url, str) </s> remove     if not isinstance(lookup_view, six.string_types):
 </s> add     if not isinstance(lookup_view, str):
    if isinstance(path, str):
  
  def find_command(cmd, path=None, pathext=None):
      if path is None:
          path = os.environ.get('PATH', '').split(os.pathsep)
    if isinstance(path, str):
          path = [path]
      # check if there are funny path extensions for executables, e.g. Windows
      if pathext is None:
          pathext = os.environ.get('PATHEXT', '.COM;.EXE;.BAT;.CMD').split(os.pathsep)
      # don't use extensions if the command ends with one of them
keep keep keep keep replace keep keep keep keep keep
 Refs #23919 -- Removed six.<various>_types usage

Thanks Tim Graham and Simon Charette for the reviews. 
django/core/management/utils.py