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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 __init_xml(self, rootElementTag):
 """Init a etree element and pop a key in there"""

        xml_root = etree.Element(rootElementTag)
        key = etree.SubElement(xml_root, "Key")
        key.text = self.apikey
        return xml_root