argument to a tzinfo method doesn't have a matching tzinfo member.
or \class{timetz} object, passing itself as the argument. A
\class{tzinfo} subclass's methods should be prepared to accept a dt
argument of \code{None} or of type \class{timetz} or
-\class{datetimetz}. If is not \code{None}, and dt.tzinfo is not
-\code{None} and not equal to self, an exception should be raised.
+\class{datetimetz}.
- utcoffset(dt)
Return offset of local time from UTC, in minutes east of UTC. If