Determines the offset to UTC in effect during a particular interval of time in the time zone this
.
The offset is the number of seconds that you add to UTC time to arrive at local time for this (ie: negative numbers for time zones west of GMT, positive numbers for east).
| this |
a TimeZone |
| interval |
an interval within the timezone |
|
the number of seconds that should be added to UTC to get the local time in this |