/usr/ is in libexttextcat-dev 3.4.3-1ubuntu1.
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/usr/include/
/usr/include/libexttextcat/
/usr/lib/
/usr/lib/pkgconfig/
/usr/lib/pkgconfig/libexttextcat.pc
/usr/lib/libexttextcat-2.0.a
/usr/share/
/usr/share/vala/
/usr/share/vala/vapi/
/usr/share/vala/vapi/libexttextcat.vapi
/usr/share/doc/
/usr/share/doc/libexttextcat-dev/
/usr/share/doc/libexttextcat-dev/copyright
/usr/include/libexttextcat/utf8misc.h
/usr/include/libexttextcat/textcat_properties.h
/usr/include/libexttextcat/textcat.h
/usr/include/libexttextcat/exttextcat-version.h
/usr/include/libexttextcat/common.h
/usr/include/libexttextcat/fingerprint.h
/usr/include/libexttextcat/constants.h
/usr/lib/libexttextcat-2.0.so
/usr/lib/libexttextcat.a
/usr/lib/libexttextcat.so
/usr/share/doc/libexttextcat-dev/TODO
/usr/share/doc/libexttextcat-dev/README
/usr/share/doc/libexttextcat-dev/changelog.Debian.gz