def number_output(
n: Union[float, int, None]) -> Optional[Union[float, int, None]]:
"""Format numbers for data series outputs"""
if n is None:
return None
if n == 0:
return 0
return sigfig_compact(n)
def test_sigfig_compact(number: float, number_expected: float) -> None:
number = sigfig_compact(number, 4)
assert number == number_expected