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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 request_slot(client, service: JID, filename: str, size: int, content_type: str):
 """ Request an HTTP upload slot. :param client: The client to request the slot with. :type client: :class:`aioxmpp.Client` :param service: Address of the HTTP upload service. :type service: :class:`~aioxmpp.JID` :param filename: Name of the file (without path), may be used by the server to generate the URL. :type filename: :class:`str` :param size: Size of the file in bytes :type size: :class:`int` :param content_type: The MIME type of the file :type content_type: :class:`str` :return: The assigned upload slot. :rtype: :class:`.xso.Slot` Sends a :xep:`363` slot request to the XMPP service to obtain HTTP PUT and GET URLs for a file upload. The upload slot is returned as a :class:`~.xso.Slot` object. """


    payload = Request(filename, size, content_type)
    return (yield from client.send(IQ(
        type_=IQType.GET,
        to=service,
        payload=payload
    )))