/usr/include/Swiften/ is in libswiften-dev 2.0+dev6-1+b1.
This file is owned by root:root, with mode 0o755.
There are a lot of files here (719 total). We're only showing the immediate contents of /usr/include/Swiften.
/usr/include/Swiften
..
/usr/include/Swiften/AdHoc/
/usr/include/Swiften/Avatars/
/usr/include/Swiften/Base/
/usr/include/Swiften/Chat/
/usr/include/Swiften/Client/
/usr/include/Swiften/Component/
/usr/include/Swiften/Compress/
/usr/include/Swiften/Config/
/usr/include/Swiften/Disco/
/usr/include/Swiften/Elements/
/usr/include/Swiften/Entity/
/usr/include/Swiften/EventLoop/
/usr/include/Swiften/FileTransfer/
/usr/include/Swiften/History/
/usr/include/Swiften/IDN/
/usr/include/Swiften/JID/
/usr/include/Swiften/Jingle/
/usr/include/Swiften/LinkLocal/
/usr/include/Swiften/MUC/
/usr/include/Swiften/Network/
/usr/include/Swiften/Parser/
/usr/include/Swiften/Presence/
/usr/include/Swiften/Queries/
/usr/include/Swiften/Roster/
/usr/include/Swiften/SASL/
/usr/include/Swiften/Serializer/
/usr/include/Swiften/Session/
/usr/include/Swiften/StreamManagement/
/usr/include/Swiften/StreamStack/
/usr/include/Swiften/StringCodecs/
/usr/include/Swiften/Swiften.h
/usr/include/Swiften/TLS/
/usr/include/Swiften/VCards/
/usr/include/Swiften/Version.h
/usr/include/Swiften/Whiteboard/