def _is_leap(year):
 return (((year % 4) == 0) and (((year % 100) != 0) or ((year % 400) == 0)))

def _is_leap ( year ) : return ( ( ( year % 4 ) == 0 ) and ( ( ( year % 100 ) != 0 ) or ( ( year % 400 ) == 0 ) ) )
year -> 1 if leap year .