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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 parse_authentication_request(self, request_body, http_headers=None):
 # type: (str, Optional[Mapping[str, str]]) -> oic.oic.message.AuthorizationRequest """ Parses and verifies an authentication request. :param request_body: urlencoded authentication request :param http_headers: http headers """


        auth_req = AuthorizationRequest().deserialize(request_body)

        for validator in self.authentication_request_validators:
            validator(auth_req)

        logger.debug('parsed authentication_request: %s', auth_req)
        return auth_req