code: def get_activation_function(activation_function_string: str):
      """
      Map the activation function from a string to the tensorflow framework equivalent
      :param activation_function_string: the type of the activation function
      :return: the tensorflow activation function
      """
      activation_functions = {
          "relu": tf.nn.relu,
          "tanh": tf.nn.tanh,
          "sigmoid": tf.nn.sigmoid,
          "elu": tf.nn.elu,
          "selu": tf.nn.selu,
          "leaky_relu": tf.nn.leaky_relu,
          "none": None,
      }
      assert (
          activation_function_string in activation_functions.keys()
      ), "Activation function must be one of the following {}. instead it was: {}".format(
          activation_functions.keys(), activation_function_string
      )
      return activation_functions[activation_function_string]
  
label_desc: Use image node_id 1 for calling a global function with example usage: get_activation_function(activation_function_string) and returns: activation_functions