code: def l2_regularizer(scale, scope=None):
      """Returns a function that can be used to apply L2 regularization to weights.
  
      Small values of L2 can help prevent overfitting the training data.
  
      Args:
        scale: A scalar multiplier `Tensor`. 0.0 disables the regularizer.
        scope: An optional scope name.
  
      Returns:
        A function with signature `l2(weights)` that applies L2 regularization.
  
      Raises:
        ValueError: If scale is negative or if scale is not a float.
      """
      if isinstance(scale, numbers.Integral):
          raise ValueError("scale cannot be an integer: %s" % (scale,))
      if isinstance(scale, numbers.Real):
          if scale < 0.0:
              raise ValueError(
                  "Setting a scale less than 0 on a regularizer: %g."
                  % scale
              )
          if scale == 0.0:
              logging.info("Scale of 0 disables regularizer.")
              return lambda _: None
  
      def l2(weights):
          """Applies l2 regularization to weights."""
          with ops.name_scope(
              scope, "l2_regularizer", [weights]
          ) as name:
              my_scale = ops.convert_to_tensor(
                  scale, dtype=weights.dtype.base_dtype, name="scale"
              )
              return standard_ops.multiply(
                  my_scale, nn.l2_loss(weights), name=name
              )
  
      return l2
  
file_path: tensornets/tensornets/contrib_layers/regularizers.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numbers
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import nn
  from tensorflow.python.ops import standard_ops
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 2 for calling a global function with example usage: l2_regularizer(scale, scope) and returns: l2, function, standard_ops