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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 _send(self, method, **parameters):
 """Sends a message to the front-end and returns a promise."""

        msg = {
            'index': self._calls,
            'method': method,
        }
        msg.update(parameters)

        promise = SimplePromise()
        self._callbacks[self._calls] = promise

        self._calls += 1
        self._comm.send(msg)

        return promise