code: def update(self, lr):
      for param in self.params:
          if param is not None:
              p = param.as_grad_stopped()
              p -= lr * param.grad.as_grad_stopped()
              param.cleargrad()
  
imports: import numpy
  import chainerx
label_desc: Use image node_id 5 for calling the Convolution2D obj's underlying member method code with example usage: obj.update(lr) without return types