docs: def register_code_edit(cls, code_edit_class):
          """
          Register an additional code edit **class**
  
          .. warning: This method expect a class, not an instance!
  
          :param code_edit_class: code edit class to register.
          """
          if not inspect.isclass(code_edit_class):
              raise TypeError('must be a class, not an instance.')
          for mimetype in code_edit_class.mimetypes:
              if mimetype in cls.editors:
                  _logger().warn('editor for mimetype already registered, '
                                 'skipping')
              cls.editors[mimetype] = code_edit_class
          _logger().log(5, 'registered editors: %r', cls.editors)