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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 handle_authn_request(self, context, binding_in):
 """ This method is bound to the starting endpoint of the authentication. :type context: satosa.context.Context :type binding_in: str :rtype: satosa.response.Response :param context: The current context :return: response """

        return self._handle_authn_request(context, binding_in, self.idp)