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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_full_xml_representation(entity, private_key):
 """Get full XML representation of an entity. This contains the <XML><post>..</post></XML> wrapper. Accepts either a Base entity or a Diaspora entity. Author `private_key` must be given so that certain entities can be signed. """

    from federation.entities.diaspora.mappers import get_outbound_entity
    diaspora_entity = get_outbound_entity(entity, private_key)
    xml = diaspora_entity.to_xml()
    return "<XML><post>%s</post></XML>" % etree.tostring(xml).decode("utf-8")