'Train using one mini-batch.
Args:
step: Training step.'

def TrainOneBatch(self, step):

    '\n                if    step    >    self.code_layer.hyperparams.switch_on_sc_alpha_after:\n                        self.code_layer.hyperparams.sc_alpha    =    1.0\n                '
    self.ForwardPropagate(train=True)
    losses = self.GetLoss(train=True)
    self.UpdateParameters(step)
    return losses
