class_docstr: Basic conv bn layer
class_docstr_tok: ["Basic","conv","bn","layer"]
code: def forward(self, x: paddle.Tensor) -> paddle.Tensor:
      x = self._conv(x)
      x = self._batch_norm(x)
      return x
  
imports: from typing import Union, List, Tuple
  import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddle.nn.layer import activation
  from paddle.nn import Conv2D, AvgPool2D
label_desc: Use image node_id 2 for calling the ConvBN obj's underlying member method code with example usage: obj.forward(x) and returns: x