The created_at field for a tweet in the Twitter REST API gives a timestamp in UTC.
If the user has configured their time zone using Twitter, the utc_offset field gives you the difference in seconds between their time zone and UTC. So,
"utc_offset":-28800
corresponds to -28800/3600 = -8 hours with UTC.
There are a couple of recommendations that don't get adjusted for daylight saving time.
Liz rice
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