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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 Shell(self, command, timeout_ms=None):
 """Run command on the device, returning the output. Args: command: Shell command to run timeout_ms: Maximum time to allow the command to run. """

        return self.protocol_handler.Command(
            self._handle, service=b'shell', command=command,
            timeout_ms=timeout_ms)