Function syntax ?

Does this syntax look correct? Can anyone think of a better way to write
this?

This function will accept two timestamp parameters and determine the highest
of the two?

create or replace function fcn_max_dt(p_dt timestamp without time zone,
p_dt2 timestamp without time zone)
returns timestamp without time zone as $$
DECLARE
v_dt timestamp without time zone;
v_dt2 timestamp without time zone;

BEGIN
v_dt := p_dt;
v_dt2 := p_dt2;

if v_dt >= v_dt2 then
return v_dt;
else
return v_dt2;
end if;

END;
$$ LANGUAGE 'plpgsql';