v = tf.Variable(0)
c = tf.constant(3)
add = tf.add(v, c)
update = tf.assign(v, add)
mul = tf.mul(add, update)
with tf.Session() as sess:
    sess.run(tf.initialize_all_variables())
res = sess.run([mul, mul])
print(res)
Tensorflow: When are variable assignments done in sess.run with a list?