my $tz = DateTime::TimeZone->new( name => $zone );
  my $dt = DateTime->new(
      year       => $year_init,
      month      => $month_init,
      day        => $day_init,
      hour       => $hour_init,
      minute     => $minutes_init,
      second     => $seconds_init,
      nanosecond => 0,
  );
$offset = $tz->offset_for_datetime($dt); #seconds
$offset_days = $offset / 86400; #days