code: def forward(self, feats):
      h, w = paddle.shape(feats)[2:4]
      out = [feats]
      for stage in self.stages:
          feats = F.avg_pool2d(
              feats, kernel_size=3, stride=2, padding="same"
          )
          upsampled = F.interpolate(
              stage(feats),
              size=[h, w],
              mode="bilinear",
              align_corners=True,
          )
          out.append(upsampled)
      return self.project(paddle.concat(out, axis=1))
  
imports: import math
  import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleseg import utils
  from paddleseg.cvlibs import manager, param_init
  from paddleseg.models import layers
label_desc: Use image node_id 2 for calling the PSPModule obj's underlying member method code with example usage: obj.forward(feats) and returns: self