Sends the request

def request(self, server=None):
        """ Sends the request """
        request = {
            "headers": {"Content-Type": "application/json"},
            "timeout": self._pump.timeout,
            "data": self.context,
        }

        url = "{proto}://{server}/{endpoint}".format(
            proto=self._pump.protocol,
            server=server or self.server,
            endpoint=self.ENDPOINT,
        )

        response = self._pump._requester(requests.post, url, **request)

        try:
            server_data = response.json()
        except ValueError:
            raise ClientException(response.content)

        if "error" in server_data:
            raise ClientException(server_data["error"], self.context)

        _log.debug("Client registration recieved: %(id)s %(secret)s %(expire)s", {
            "id": server_data["client_id"],
            "secret": server_data["client_secret"],
            "expire": server_data["expires_at"],
        })

        return server_data