code: def subtract_and_get(self, delta):
          '''
          Atomically subtracts `delta` from the current value.
  
          :param delta: The delta to subtract.
          '''
          with self._reference.get_lock():
              self._reference.value -= delta
              return self._reference.valuf subtract_and_get(self, delta):
          '''
          Atomically subtracts `delta` from the current value.
  
          :param delta: The delta to subtract.
          '''
          with self._reference.get_lock():
              self._reference.value -= delta
              return self._reference.value
docs: Atomically subtracts `delta` from the current value.
  
          :param delta: The delta to subtract.