pub fn errors(
  network: ZList(ZList(Neuron)),
  input_val: ZList(Float),
  expected_output: ZList(Float),
  in_parallel: Bool,
) -> ZList(Float)

pub fn fit(
  network: ZList(ZList(Neuron)),
  learning_rate: Float,
  input_val: ZList(Float),
  expected_output: ZList(Float),
  in_parallel: Bool,
) -> ZList(ZList(Neuron))

pub fn generator(
  layer_sizes: ZList(Int),
) -> Generator(ZList(ZList(Neuron)))

pub fn init(
  layer_sizes: ZList(Int),
  activation_f: fn(Int) -> Activation,
  weight_init_f: fn(Int) -> Float,
) -> ZList(ZList(Neuron))

pub fn output(
  network: ZList(ZList(Neuron)),
  input_val: ZList(Float),
  in_parallel: Bool,
) -> ZList(Float)