code: def on_epoch_end(self, **kwargs):
          "step the rest of the accumulated grads if not perfectly divisible"
          for p in (self.learn.model.parameters()):
                  if p.requires_grad: p.grad.div_(self.acc_samples)
          if not self.drop_last: self.learn.opt.step()
          self.learn.opt.zero_grad(f on_epoch_end(self, **kwargs):
          "step the rest of the accumulated grads if not perfectly divisible"
          for p in (self.learn.model.parameters()):
                  if p.requires_grad: p.grad.div_(self.acc_samples)
          if not self.drop_last: self.learn.opt.step()
          self.learn.opt.zero_grad()
docs: step the rest of the accumulated grads if not perfectly divisible