The POSIX standard provides three functions for converting between integer
epoch values and 6-component "broken-down" time representations.
localtime and gmtime convert an epoch into the 6 components of seconds,
minutes, hours, day of month, month and year, in either local timezone or UTC.
The mktime function converts a local broken-down time into an epoch value.
However, POSIX does not provide a UTC version of this.

This module provides a function timegm which has this ability.

WWW: https://metacpan.org/pod/Time::timegm