'Call all handlers subscribed to an event.
:type event_name: str
:param event_name: The name of the event to emit.
:type **kwargs: dict
:param **kwargs: Arbitrary kwargs to pass through to the
subscribed handlers.  The ``event_name`` will be injected
into the kwargs so it\'s not necesary to add this to **kwargs.
:rtype: list of tuples
:return: A list of ``(handler_func, handler_func_return_value)``'

def emit(self, event_name, **kwargs):

    return []
