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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _create_placeholders(self):
 """Create the computational graph's placeholders."""

        self.input_data = tf.placeholder(
            tf.int32, [self.batch_size, self.num_steps])
        self.input_labels = tf.placeholder(
            tf.int32, [self.batch_size, self.num_steps])