code: def set_training(train_mode): #pylint: disable=redefined-outer-name
      
      prev = ctypes.c_int()
      check_call(_LIB.MXAutogradSetIsTraining(
          ctypes.c_int(train_mode), ctypes.byref(prev)))
      return bool(prev.value)
docs: Set status to training/predicting. This affects ctx.is_train in operator
      running context. For example, Dropout will drop inputs randomly when
      train_mode=True while simply passing through if train_mode=False.
  
      Parameters
      ----------
      train_mode: bool
  
      Returns
      -------
      previous state before this set.