(self, dt)
datetime -> string name of time zone.
datetime -> string name of time zone.
datetime - > string name of time zone .
def tzname(self, dt):
        "datetime -> string name of time zone."
        raise NotImplementedError("tzinfo subclass must override tzname()")
def tzname ( self , dt ) : raise NotImplementedError ( "tzinfo subclass must override tzname()" )