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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 sign_assertion(self, statement, **kwargs):
 """Sign a SAML assertion. See sign_statement() for the kwargs. :param statement: The statement to be signed :return: The signed statement """

        return self.sign_statement(
                statement, class_name(saml.Assertion()), **kwargs)