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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 gen_paula_etree(paula_id):
 """ creates an element tree representation of an empty PAULA XML file. """

    E = ElementMaker(nsmap=NSMAP)
    tree = E('paula', version='1.1')
    tree.append(E('header', paula_id=paula_id))
    return E, tree