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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 _get_engine(self, engine):
 """ Load an engine """

        if engine in self._engines:
            return self._engines[engine]

        if engine == "vmware":
            self._engines["vmware"] = VMwareGNS3VM(self._controller)
            return self._engines["vmware"]
        elif engine == "virtualbox":
            self._engines["virtualbox"] = VirtualBoxGNS3VM(self._controller)
            return self._engines["virtualbox"]
        elif engine == "remote":
            self._engines["remote"] = RemoteGNS3VM(self._controller)
            return self._engines["remote"]
        raise NotImplementedError("The engine {} for the GNS3 VM is not supported".format(engine))