def find_dialogue_event(dialogue_event_name, dialogue_event_defs):
    """ Find a dialogue event by name in a list of dialogue event definitions.

    :param dialogue_event_name: the name of the dialogue event to look for.
    :param dialogue_event_defs: a list of dialogue event definitions.
    :return: the dialogue_event_def with matching name, or None.
    """
    for dialogue_event_def in dialogue_event_defs:
        if dialogue_event_def.name == dialogue_event_name:
            return dialogue_event_def
    return None