code: def _pp_module(x, psp_size):
      n, c, h, w = x.shape
      priors = []
      for size in psp_size:
          feat = F.adaptive_avg_pool2d(x, size)
          feat = paddle.reshape(feat, shape=(0, c, -1))
          priors.append(feat)
      center = paddle.concat(priors, axis=-1)
      return center
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleseg.cvlibs import manager
  from paddleseg.models import layers
  from paddleseg.utils import utils
label_desc: Use image node_id 1 for calling a global function with example usage: _pp_module(x, psp_size) and returns: center