TimeZoneOffset

TimeZoneOffset[tz] gives the numeric offset between the time zone tz and GMT on the current date.

TimeZoneOffset[loc] gives the numeric offset between the time zone for the location loc and GMT.

TimeZoneOffset[tz,base] gives the numeric offset between tz and the specified base time zone.

TimeZoneOffset[tz,date] gets a list of possible time zone offsets for tz at the given date list.

TimeZoneOffset[tz,base,date] gives the numeric offset between tz and base on the specified date.

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