Function pio_to_normalized 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn pio_to_normalized(
    net: *const PioNetwork,
    errbuf: *mut c_char,
    errlen: usize,
) -> *mut PioNetwork

Normalize net into a NEW per-unit network handle: per unit, radians, out-of-service filtered, source bus ids preserved, bus types canonicalized (see Network::to_normalized). The result is independent of net; free both with pio_network_free. Every extractor and pio_to_json works on it unchanged (the handle is per unit, not MW). Returns NULL on error (no reference bus can be chosen, or a non-positive base MVA) and writes the message into errbuf.