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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 create_payload(self):
 """Create the payload doc. Returns: str """

        doc = etree.fromstring(self.message)
        self.payload = etree.tostring(doc, encoding="utf-8")
        self.payload = urlsafe_b64encode(self.payload).decode("ascii")
        return self.payload