Answer by pfm for How to feed a local placeholder of some function from main function?

If you want to access a placeholder or a tensor directly you can call get_tensor_by_name:

import tensorflow as tf

def f():
    a=tf.placeholder(dtype=tf.float32, name='name_a')
    b=tf.placeholder(dtype=tf.float32, name='name_b')
    addition=tf.add(a,b)
    return addition

if __name__ == '__main__':
    var = f()
    a = tf.get_default_graph().get_tensor_by_name('name_a:0')
    b = tf.get_default_graph().get_tensor_by_name('name_b:0')
    with tf.Session() as sess:
        print(sess.run(var, feed_dict={a:[1],b:[2]}))

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