How to use the synapse.api.constants.Membership function in synapse

now = (now // 1000 // self.stats_bucket_size) * self.stats_bucket_size

            if typ == EventTypes.Member:
                # we could use _get_key_change here but it's a bit inefficient
                # given we're not testing for a specific result; might as well
                # just grab the prev_membership and membership strings and
                # compare them.
                prev_event_content = {}
                if prev_event_id is not None:
                    prev_event = yield self.store.get_event(
                        prev_event_id, allow_none=True
                    )
                    if prev_event:
                        prev_event_content = prev_event.content

                membership = event_content.get("membership", Membership.LEAVE)
                prev_membership = prev_event_content.get("membership", Membership.LEAVE)

                if prev_membership == membership:
                    continue

                if prev_membership == Membership.JOIN:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "joined_members", -1
                    )
                elif prev_membership == Membership.INVITE:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "invited_members", -1
                    )
                elif prev_membership == Membership.LEAVE:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "left_members", -1

def test_rooms_members_other(self):
        self.other_id = "@zzsid1:red"
        path = "/rooms/%s/state/m.room.member/%s" % (
            urlparse.quote(self.room_id),
            self.other_id,
        )

        # valid invite message
        content = '{"membership":"%s"}' % Membership.INVITE
        request, channel = self.make_request("PUT", path, content)
        self.render(request)
        self.assertEquals(200, channel.code, msg=channel.result["body"])

        request, channel = self.make_request("GET", path, None)
        self.render(request)
        self.assertEquals(200, channel.code, msg=channel.result["body"])
        self.assertEquals(json.loads(content), channel.json_body)

def test_invited_permissions(self):
        room = self.created_rmid
        self.helper.invite(room=room, src=self.rmcreator_id, targ=self.user_id)

        # set [invite/join/left] of other user, expect 403s
        self.helper.invite(
            room=room, src=self.user_id, targ=self.rmcreator_id, expect_code=403
        )
        self.helper.change_membership(
            room=room,
            src=self.user_id,
            targ=self.rmcreator_id,
            membership=Membership.JOIN,
            expect_code=403,
        )
        self.helper.change_membership(
            room=room,
            src=self.user_id,
            targ=self.rmcreator_id,
            membership=Membership.LEAVE,
            expect_code=403,
        )

def handle_room(event):
            d = {
                "room_id": event.room_id,
                "membership": event.membership,
                "visibility": (
                    "public" if event.room_id in public_room_ids else "private"
                ),
            }

            if event.membership == Membership.INVITE:
                time_now = self.clock.time_msec()
                d["inviter"] = event.sender

                invite_event = yield self.store.get_event(event.event_id)
                d["invite"] = yield self._event_serializer.serialize_event(
                    invite_event, time_now, as_client_event
                )

            rooms_ret.append(d)

            if event.membership not in (Membership.JOIN, Membership.LEAVE):
                return

            try:
                if event.membership == Membership.JOIN:
                    room_end_token = now_token.room_key

is_host_in_room = yield self._is_host_in_room(current_state_ids)

        if effective_membership_state == Membership.JOIN:
            if requester.is_guest:
                guest_can_join = yield self._can_guest_join(current_state_ids)
                if not guest_can_join:
                    # This should be an auth check, but guests are a local concept,
                    # so don't really fit into the general auth process.
                    raise AuthError(403, "Guest access not allowed")

            if not is_host_in_room:
                inviter = yield self._get_inviter(target.to_string(), room_id)
                if inviter and not self.hs.is_mine(inviter):
                    remote_room_hosts.append(inviter.domain)

                content["membership"] = Membership.JOIN

                profile = self.profile_handler
                if not content_specified:
                    content["displayname"] = yield profile.get_displayname(target)
                    content["avatar_url"] = yield profile.get_avatar_url(target)

                if requester.is_guest:
                    content["kind"] = "guest"

                ret = yield self._remote_join(
                    requester, remote_room_hosts, room_id, target, content
                )
                defer.returnValue(ret)

        elif effective_membership_state == Membership.LEAVE:
            if not is_host_in_room:

Args:
            user_id (str)
            writer (ExfiltrationWriter)

        Returns:
            defer.Deferred: Resolves when all data for a user has been written.
            The returned value is that returned by `writer.finished()`.
        """
        # Get all rooms the user is in or has been in
        rooms = yield self.store.get_rooms_for_user_where_membership_is(
            user_id,
            membership_list=(
                Membership.JOIN,
                Membership.LEAVE,
                Membership.BAN,
                Membership.INVITE,
            ),
        )

        # We only try and fetch events for rooms the user has been in. If
        # they've been e.g. invited to a room without joining then we handle
        # those seperately.
        rooms_user_has_been_in = yield self.store.get_rooms_user_has_been_in(user_id)

        for index, room in enumerate(rooms):
            room_id = room.room_id

            logger.info(
                "[%s] Handling room %s, %d/%d", user_id, room_id, index + 1, len(rooms)
            )

            forgotten = yield self.store.did_forget(user_id, room_id)

membership = event_content.get("membership", Membership.LEAVE)
                prev_membership = prev_event_content.get("membership", Membership.LEAVE)

                if prev_membership == membership:
                    continue

                if prev_membership == Membership.JOIN:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "joined_members", -1
                    )
                elif prev_membership == Membership.INVITE:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "invited_members", -1
                    )
                elif prev_membership == Membership.LEAVE:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "left_members", -1
                    )
                elif prev_membership == Membership.BAN:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "banned_members", -1
                    )
                else:
                    err = "%s is not a valid prev_membership" % (repr(prev_membership),)
                    logger.error(err)
                    raise ValueError(err)

                if membership == Membership.JOIN:
                    yield self.store.update_stats_delta(
                        now, "room", room_id, "joined_members", +1
                    )

def forget(self, user, room_id):
        user_id = user.to_string()

        member = yield self.state_handler.get_current_state(
            room_id=room_id,
            event_type=EventTypes.Member,
            state_key=user_id
        )
        membership = member.membership if member else None

        if membership is not None and membership not in [
            Membership.LEAVE, Membership.BAN
        ]:
            raise SynapseError(400, "User %s in room %s" % (
                user_id, room_id
            ))

        if membership:
            yield self.store.forget(user_id, room_id)

context = yield self._handle_new_event(origin, event, state=state)
        except AuthError as e:
            raise FederationError("ERROR", e.code, e.msg, affected=event.event_id)

        room = yield self.store.get_room(room_id)

        if not room:
            try:
                yield self.store.store_room(
                    room_id=room_id, room_creator_user_id="", is_public=False
                )
            except StoreError:
                logger.exception("Failed to store room.")

        if event.type == EventTypes.Member:
            if event.membership == Membership.JOIN:
                # Only fire user_joined_room if the user has acutally
                # joined the room. Don't bother if the user is just
                # changing their profile info.
                newly_joined = True

                prev_state_ids = yield context.get_prev_state_ids(self.store)

                prev_state_id = prev_state_ids.get((event.type, event.state_key))
                if prev_state_id:
                    prev_state = yield self.store.get_event(
                        prev_state_id, allow_none=True
                    )
                    if prev_state and prev_state.membership == Membership.JOIN:
                        newly_joined = False

                if newly_joined:

requester=target_requester,
                    target=target_requester.user,
                    room_id=room_id,
                    action=Membership.LEAVE,
                    content={},
                    ratelimit=False,
                    require_consent=False,
                )

                yield self.room_member_handler.forget(target_requester.user, room_id)

                yield self.room_member_handler.update_membership(
                    requester=target_requester,
                    target=target_requester.user,
                    room_id=new_room_id,
                    action=Membership.JOIN,
                    content={},
                    ratelimit=False,
                    require_consent=False,
                )

                kicked_users.append(user_id)
            except Exception:
                logger.exception(
                    "Failed to leave old room and join new room for %r", user_id,
                )
                failed_to_kick_users.append(user_id)

        yield self.event_creation_handler.create_and_send_nonmember_event(
            room_creator_requester,
            {
                "type": "m.room.message",