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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 mask_loss(input_tensor, binary_tensor):
 """ Mask a loss by using a tensor filled with 0 or 1. """

    with tf.variable_scope("mask_loss"):
        mask = tf.cast(tf.cast(binary_tensor, tf.bool), tf.float32)

        return input_tensor * mask