= choice [ zonedTimeToUTC <$> try rfc1123DateAndTime
, zonedTimeToUTC <$> try rfc733DateAndTime
, zonedTimeToUTC <$> try rfc822DateAndTime
= choice [ zonedTimeToUTC <$> try rfc1123DateAndTime
, zonedTimeToUTC <$> try rfc733DateAndTime
, zonedTimeToUTC <$> try rfc822DateAndTime