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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 add_qemu_path(self, instance):
 """ Add the qemu path to the hypervisor conf data :param instance: Hypervisor instance """

        tmp_conf = {'qemu_path': self.old_top[instance]['qemupath']}
        if len(self.topology['conf']) == 0:
            self.topology['conf'].append(tmp_conf)
        else:
            self.topology['conf'][self.hv_id].update(tmp_conf)