code: def forward(self, features):
      h, w = features.size()[2], features.size()[3]
      pyramids = [features]
      pyramids.extend(
          [
              F.interpolate(
                  stage(features),
                  size=(h, w),
                  mode="bilinear",
                  align_corners=True,
              )
              for stage in self.stages
          ]
      )
      output = self.bottleneck(torch.cat(pyramids, dim=1))
      return output
  
imports: import torch
  import logging
  import torch.nn
  import torch.nn.functional
  from torchvision import models
  from itertools import chain
  import numpy
  from collections import OrderedDict
label_desc: Use image node_id 3 for calling the PSPModule obj's underlying member method code with example usage: obj.forward(features) and returns: output