(self)
This method should be implemented by all subclasses of CommCareMobileContactMixin,
        and must return a string representation of the time zone. For example, "America/New_York".
This method should be implemented by all subclasses of CommCareMobileContactMixin,
        and must return a string representation of the time zone. For example, "America/New_York".
This method should be implemented by all subclasses of CommCareMobileContactMixin and must return a string representation of the time zone . For example America / New_York .
def get_time_zone(self):
        """
        This method should be implemented by all subclasses of CommCareMobileContactMixin,
        and must return a string representation of the time zone. For example, "America/New_York".
        """
        raise NotImplementedError("Subclasses of CommCareMobileContactMixin must implement method get_time_zone().")
def get_time_zone ( self ) : raise NotImplementedError ( "Subclasses of CommCareMobileContactMixin must implement method get_time_zone()." )