parameters: (self, options, options_class_name)
docstring: Initialize the descriptor given its options message and the name of the
      class of the options message. The name of the class is required in case
      the options message is None and has to be created.
docstring_summary: Initialize the descriptor given its options message and the name of the
      class of the options message. The name of the class is required in case
      the options message is None and has to be created.
docstring_tokens: Initialize the descriptor given its options message and the name of the class of the options message . The name of the class is required in case the options message is None and has to be created .
function: def __init__(self, options, options_class_name):
      """Initialize the descriptor given its options message and the name of the
      class of the options message. The name of the class is required in case
      the options message is None and has to be created.
      """
      self._options = options
      self._options_class_name = options_class_name
  
      # Does this descriptor have non-default options?
      self.has_options = options is not None
function_tokens: def __init__ ( self , options , options_class_name ) : self . _options = options self . _options_class_name = options_class_name # Does this descriptor have non-default options? self . has_options = options is not None