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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 get_http_body(req, content_type=URL_ENCODED):
 """ Get the message into the format that should be places in the body part of a HTTP request. :param req: The service request as a :py:class:`oidcmsg.message.Message` instance :param content_type: The format of the body part. :return: The correctly formatet service request. """

    if URL_ENCODED in content_type:
        return req.to_urlencoded()
    elif JSON_ENCODED in content_type:
        return req.to_json()
    elif JOSE_ENCODED in content_type:
        return req  # already packaged
    else:
        raise UnSupported(
            "Unsupported content type: '%s'" % content_type)