code: def l2_regularizer(weight=1.0, scope=None):
    
    def regularizer(tensor):
      with tf.name_scope(scope, 'L2Regularizer', [tensor]):
        l2_weight = tf.convert_to_tensor(weight,
                                         dtype=tensor.dtype.base_dtype,
                                         name='weight')
        return tf.multiply(l2_weight, tf.nn.l2_loss(tensor), name='value')
    return regularizer
docs: Define a L2 regularizer.
  
    Args:
      weight: scale the loss by this factor.
      scope: Optional scope for name_scope.
  
    Returns:
      a regularizer function.