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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 l1_distance(t1, t2, name=None):
 """l1 distance between t1 and t2. Args: t1: A tensor. t2: A tensor that is the same size as t1. name: Optional name for this op. Returns: The l1 distance between t1 and t2. """

  with tf.name_scope(name, 'l1_distance', [t1, t2]) as scope:
    t1 = tf.convert_to_tensor(t1, name='t1')
    t2 = tf.convert_to_tensor(t2, name='t2')
    sub = tf.subtract(t1, t2)
    reduction_dim = _last_index(sub, 1)
    return tf.reduce_sum(tf.abs(sub), reduction_dim, name=scope)