Function create_subject 

pub fn create_subject<'a>(
    account: &'a str,
    attributes: Option<SubjectAttributes<'a>>,
    pds_did: &'a str,
    pds_hostname: &'a str,
    kind: SubjectKind<'a>,
    asked: Asked,
    (pool, zone): (&'a str, &'a str),
    (name, label): (Option<&'a str>, Option<&'a str>),
    now: OffsetDateTime,
) -> Subject<'a>

Builds the Subject::Create a gate judges for one pool and zone a create could land in. attributes is the creating account’s, when this server hosts it; name and label are set when the create gave a name.