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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 _ubridge_send(self, command):
 """ Sends a command to uBridge hypervisor. :param command: command to send """


        if not self._ubridge_hypervisor or not self._ubridge_hypervisor.is_running():
            yield from self._start_ubridge()
        if not self._ubridge_hypervisor or not self._ubridge_hypervisor.is_running():
            raise NodeError("Cannot send command '{}': uBridge is not running".format(command))
        try:
            yield from self._ubridge_hypervisor.send(command)
        except UbridgeError as e:
            raise UbridgeError("{}: {}".format(e, self._ubridge_hypervisor.read_stdout()))