Look at the code snippet：
import tensorflow as tf
with tf.name_scope('y'):
a1 = tf.Variable(1,name='a')
with tf.name_scope('y'):
a2 = tf.Variable(1,name='b')
print(a1.name)
print(a2.name)
The output is
y/a:0
y_1/b:0
Why the the name_scope of variable a2 is y_1?