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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 l2_loss(tensor, weight=1.0, scope=None):
 """Define a L2Loss, useful for regularize, i.e. weight decay. Args: tensor: tensor to regularize. weight: an optional weight to modulate the loss. scope: Optional scope for name_scope. Returns: the L2 loss op. """

  with tf.name_scope(scope, 'L2Loss', [tensor]):
    weight = tf.convert_to_tensor(weight,
                                  dtype=tensor.dtype.base_dtype,
                                  name='loss_weight')
    loss = tf.multiply(weight, tf.nn.l2_loss(tensor), name='value')
    tf.add_to_collection(LOSSES_COLLECTION, loss)
    return loss