pub fn accuracy(
  y_hats_with_ys: Iterator(#(ZList(Float), ZList(Float))),
) -> Float

pub fn dot_product(
  left: ZList(Float),
  right: ZList(Float),
) -> Float

pub fn exp(x: Float) -> Float

pub fn log(x: Float) -> Float

pub fn root_mean_square_error(
  y_hats_with_ys: Iterator(#(ZList(Float), ZList(Float))),
) -> Float

pub fn tanh(x: Float) -> Float