code: def round_grad(x):
      idx = tf.cast(tf.round(x), tf.int32)
  
      def grad(dy):
          """Let gradients pass through."""
          return dy
  
      return idx, grad
  
imports: import tensorflow.compat.v1
label_desc: Use image node_id 4 for calling a global function with example usage: round_grad(x) and returns: idx,  grad, dy