one, tag with the zone category. It also supports multiple classes
        of zones simply by adding aliases to the command key.

        Credits: Darren @ 7th Sea MUSH.
    """

    key = "zone"
    aliases = ("area","region")
    help_category = "Building"
    switch_options = ('clear',)
    locks = "perm(Builder)"

    def func(self):
        caller = self.caller

        # If they called the command without any args, display a usage
        # message and quit.
        if not self.args:
            caller.msg("Usage: %s[/clear] <room>[=<%s>]" % (self.cmdstring, self.cmdstring))
            return

        # Find the object they're trying to zone.
        obj = caller.search(self.lhs)

        # If no object was found, we can just quit because search() will
        # have already handled displaying the error message.
        if not obj:
            return

        # Ensure that the target object is a room. Note that this is a
        # design choice and not a limitation of the system! Zones are just
        # tags and all typeclasses can have tags.
        if not utils.inherits_from(obj, "typeclasses.rooms.Room"):
            caller.msg("Only rooms should have %ss." % self.cmdstring)
            return

        # Ensure the caller has permission to modify the room.
        if not (obj.access(caller, "control") or obj.access(caller, "edit")):
            self.caller.msg("You don't have permission to change the %s of %s." % (self.cmdstring, obj.get_display_name(caller)))
            return

        # Are we just clearing?
        just_clearing = ("clear" in self.switches) if self.switches else False

        # Now let's check to see if there is a zone already set.
        tmp = obj.tags.get(category=self.cmdstring, return_list=True)
        old_zone = tmp[0] if tmp else None

        # Now let's deal with the new zone name. Since zones are tags and
        # tags cannot contain spaces, we'll make things easier for our
        # builders by automatically converting any spaces into underscores.
        # We use split() and join() here rather than replace() to make sure that
        # all of the words of the zone name are seperated by a single space.
        zone = "_".join(self.rhs.split()) if self.rhs else None

        # Now let's handle removing the old zone.
        if (old_zone and zone) or just_clearing:
            if old_zone:
                obj.tags.remove(old_zone, category=self.cmdstring)
                caller.msg("Existing %s \"|w%s|n\" removed from |w%s|n." % (self.cmdstring, old_zone, obj.get_display_name(caller)))
            else:
                caller.msg("There is no old %s to clear." % self.cmdstring)

            if just_clearing:
                return

        if zone:
            # Set the new zone.
            obj.tags.add(zone, category=self.cmdstring)
            caller.msg("%s of |w%s|n set to \"|w%s|n\"." % (self.cmdstring.capitalize(), obj.get_display_name(caller), zone))
        else:
            # No new zone was given, just display the current zone (if any).
            if old_zone:
                caller.msg("The %s of |w%s|n is \"|w%s|n\"." % (self.cmdstring, obj.get_display_name(caller), old_zone))
            else:
                caller.msg("Room |w%s|n has no %s set." % (obj.get_display_name(caller), self.cmdstring))