Macro datetime 

macro_rules! datetime {
    ($y:literal-$m:literal-$d:literal $h:literal : $mi:literal : $s:literal) => { ... };
    ($y:literal-$m:literal-$d:literal $h:literal : $mi:literal : $s:literal $($tz:ident)::+) => { ... };
}

Construct a date and time from a YYYY-MM-DD HH:MM:SS literal.