code: def fprop(self, x):
      return tf.reshape(x, [-1, self.output_width])
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numpy
  import tensorflow
  from cleverhans.serial import NoRefModel
label_desc: Use image node_id 3 for calling the Flatten obj's underlying member method code with example usage: obj.fprop(x) and returns: tf