fermat97:

tf.keras.backend.epsilon()


I agree that this would be overkill. It’s literally just
@tf_export('keras.backend.epsilon')
def epsilon():
  """Returns the value of the fuzz factor used in numeric expressions.
  Returns:
      A float.
  """
  return _EPSILON

(Source: https://github.com/tensorflow/tensorflow/blob/r1.12/tensorflow/python/keras/backend.py 43)
where _EPSILON = 1e-7.