Function normalize_args 

pub fn normalize_args<I, K>(
    args: I,
) -> Result<Vec<(String, String)>, IdentityError>
where
    I: IntoIterator<Item = (K, ArgValue)>,
    K: Into<String>,

Normalize a record of key arguments: omit absent values, spell scalars the JavaScript way, and sort names by UTF-16 code units.

The sort is stable, so entries whose names compare equal keep their input order.