A very simple tensorflow example that demonstrates bad type conversion during py_func results processing

py_func_failure.py

import tensorflow as tf

def test_func(x):
    """ Builds a list of ints with length `x`.
    """
    return [i for i in range(x)],


def main():
    t0 = tf.constant(0, dtype=tf.int64)
    t0 = tf.py_func(test_func, [t0], tf.int64)

    t1 = tf.constant(1, dtype=tf.int64)
    t1 = tf.py_func(test_func, [t1], tf.int64)

    with tf.Session() as sess:
        sess.run(t1)            # OK
        sess.run(t0)            # 0-th value is double, expects int64

if __name__ == "__main__":
    print(tf.GIT_VERSION, tf.VERSION)
    main()