Function utc_time_fields_valid 

pub exec fn utc_time_fields_valid(bytes: &[u8], has_seconds: bool) -> bool

requires

if has_seconds { 12 <= bytes.len() } else { 10 <= bytes.len() },

returns

utc_time_fields_wf(bytes@, has_seconds),

Verified executable implementation of utc_time_fields_wf.