docstr: x shape :[ batch, time, dim]
  output shape: [batch, dim]
code: def call(self, x):
      """
      x shape :[ batch, time, dim]
      output shape: [batch, dim]
      """
      x = self.time_pool(x)
      x = self.reshape(x)
      return x
  
imports: import numpy
  from absl import logging
  import delta.compat
  from tensorflow.python.keras import backend
  from delta.models.base_model import Model
  from delta.layers.base_layer import Layer
  from delta import utils
  from delta.utils.register import registers
label_desc: Use image node_id 3 for calling the TimePool obj's underlying member method code with example usage: obj.call(x) and returns: x