Set the number of vCPU cores for the GNS3 VM.

        :param vcpus: number of vCPU cores

def set_vcpus(self, vcpus):
        """
        Set the number of vCPU cores for the GNS3 VM.

        :param vcpus: number of vCPU cores
        """

        yield from self._execute("modifyvm", [self._vmname, "--cpus", str(vcpus)], timeout=3)
        log.info("GNS3 VM vCPU count set to {}".format(vcpus))