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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def recipients(messenger, addresses):
 """Structures recipients data. :param str|unicode, MessageBase messenger: MessengerBase heir :param list[str|unicode]|str|unicode addresses: recipients addresses or Django User model heir instances (NOTE: if supported by a messenger) :return: list of Recipient :rtype: list[Recipient] """

    if isinstance(messenger, six.string_types):
        messenger = get_registered_messenger_object(messenger)
    return messenger._structure_recipients_data(addresses)