Session 2

import tensorflow as tf

import os

# Just disables the warning, doesn't enable AVX/FMA
os.environ['TF_CPP_MIN_LOG_LEVEL'] = '2'
a = tf.constant(1.2)
b = tf.constant(2.8)
c = a + b
c
<tf.Tensor 'add:0' shape=() dtype=float32>
# You can see the value is not updated as it is just a model
with tf.Session() as sess:
    print(sess.run(c))
    print(c)
4.0
Tensor("add:0", shape=(), dtype=float32)
c
<tf.Tensor 'add:0' shape=() dtype=float32>