def handle_other(self, response):
        """Handles all responses with the exception of 401s.

        This is necessary so that we can authenticate responses if requested"""

        log.debug("handle_other(): Handling: %d" % response.status_code)

        if self.mutual_authentication in (REQUIRED, OPTIONAL) and not self.auth_done:

            is_http_error = response.status_code >= 400

            if _negotiate_value(response) is not None:
                log.debug("handle_other(): Authenticating the server")
                if not self.authenticate_server(response):
                    # Mutual authentication failure when mutual auth is wanted,
                    # raise an exception so the user doesn't use an untrusted
                    # response.
                    log.error("handle_other(): Mutual authentication failed")
                    raise MutualAuthenticationError("Unable to authenticate "
                                                    "{0}".format(response))

                # Authentication successful
                log.debug("handle_other(): returning {0}".format(response))
                self.auth_done = True
                return response

            elif is_http_error or self.mutual_authentication == OPTIONAL:
                if not response.ok:
                    log.error("handle_other(): Mutual authentication unavailable "
                              "on {0} response".format(response.status_code))

                if(self.mutual_authentication == REQUIRED and
                       self.sanitize_mutual_error_response):
                    return SanitizedResponse(response)
                else:
                    return response
            else:
                # Unable to attempt mutual authentication when mutual auth is
                # required, raise an exception so the user doesn't use an
                # untrusted response.
                log.error("handle_other(): Mutual authentication failed")
                raise MutualAuthenticationError("Unable to authenticate "
                                                "{0}".format(response))
        else:
            log.debug("handle_other(): returning {0}".format(response))
            return response
Handles all responses with the exception of 401s.

        This is necessary so that we can authenticate responses if requested