code: def __call__(self, x):
      assert isinstance(x, dy.Expression)
  
      self.W = dy.parameter(
          self.pW
      )  # add parameters to graph as expressions # m2.add_parameters((8, len(inputs)))
      self.b = dy.parameter(self.pb)
      self.x = x
  
      return self.W * self.x + self.b
  
file_path: dynet/examples/variational-autoencoder/basic-image-recon/vae.py
imports: from __future__ import print_function
  from utils import load_mnist, make_grid, pre_pillow_float_img_process, save_image
  import numpy
  import argparse
  import dynet
  import os
  import time
label_desc: Use image node_id 2 for calling the DynetLinear obj's underlying member method code with example usage: obj.__call__(x) and returns: unknown