Function parse_iso8601_utc 

pub fn parse_iso8601_utc(s: &str) -> Result<SystemTime>

Strict parser for the canonical timestamp form (§4.1), accepting the legacy second-precision form for rows written by older crate versions.

Both this and format_iso8601_utc delegate to crate::util::timestamp, which owns the canonical form. They remain here as the names §5.1.1 uses.