let time_zone = tzdb::local_tz()?;       // tz::TimeZoneRef<'_>
let current_time = tzdb::now::local()?;  // tz::DateTime

// access by identifier
let time_zone = tzdb::time_zone::europe::KYIV;
let current_time = tzdb::now::in_tz(tzdb::time_zone::europe::KYIV)?;

// access by name
let time_zone = tzdb::tz_by_name("Europe/Berlin")?;
let current_time = tzdb::now::in_named("Europe/Berlin")?;

// names are case insensitive
let time_zone = tzdb::tz_by_name("ArCtIc/LongYeArByEn")?;
let current_time = tzdb::now::in_named("ArCtIc/LoNgYeArByEn")?;

// provide a default time zone
let current_time = tzdb::now::local_or(tzdb::time_zone::GMT)?;
let current_time = tzdb::now::in_named_or(tzdb::time_zone::GMT, "Some/City")?;