code: def _look_for_vboxnet(self, interface_number):
          
  
          result = yield from self._execute("showvminfo", [self._vmname, "--machinereadable"])
          for info in result.splitlines():
              if '=' in info:
                  name, value = info.split('=', 1)
                  if name == "hostonlyadapter{}".format(interface_number):
                      return value.strip('"')
          return None
docs: Look for the VirtualBox network name associated with a host only interface.
  
          :returns: None or vboxnet name