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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_message_content(self):
 """ Given the Slap XML, extract out the payload. """

        body = self.doc.find(
            ".//{http://salmon-protocol.org/ns/magic-env}data").text

        body = urlsafe_b64decode(body.encode("ascii"))

        logger.debug("diaspora.protocol.get_message_content: %s", body)
        return body