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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Ch 02
Step1:  Define an op to dequeue a line from file
Step2:  Start all queue runners collected in the graph
Step3:  Try reading lines from the file by dequeuing
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Python Code:
import tensorflow as tf
filename_queue = tf.train.string_input_producer(["big.txt"])
Explanation: Ch 02: Concept 10
Queue of text from file
The previous notebook (Concept 09) introduced queues. Let's see how we can use them with real world data.
Download a corpus of text.
$ wget http://norvig.com/big.txt
Create a queue of filenames:
End of explanation
reader = tf.TextLineReader()
key_op, value_op = reader.read(filename_queue)
Explanation: Define an op to dequeue a line from file:
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sess = tf.InteractiveSession()
coord = tf.train.Coordinator()
threads = tf.train.start_queue_runners(coord=coord)
Explanation: Start all queue runners collected in the graph:
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for i in range(100):
    key, value = sess.run([key_op, value_op])
    print(key, value)
Explanation: Try reading lines from the file by dequeuing:
End of explanation
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