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# Licensed under the Apache License, Version 2.0 (the "License");
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#     http://www.apache.org/licenses/LICENSE-2.0
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"""Gaussian error linear unit."""

import tensorflow as tf, tf_keras


@tf_keras.utils.register_keras_serializable(package='Text')
def gelu(x):
  """Gaussian Error Linear Unit.

  This is a smoother version of the RELU.
  Original paper: https://arxiv.org/abs/1606.08415
  Args:
    x: float Tensor to perform activation.

  Returns:
    `x` with the GELU activation applied.
  """
  return tf_keras.activations.gelu(x, approximate=True)