/usr/share/sip/PyQt5/QtWebKit/ is in pyqt5-dev 5.7+dfsg-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/sip/PyQt5/QtWebKit/QtWebKitmod.sip
/usr/share/sip/PyQt5/QtWebKit/qwebdatabase.sip
/usr/share/sip/PyQt5/QtWebKit/qwebelement.sip
/usr/share/sip/PyQt5/QtWebKit/qwebhistory.sip
/usr/share/sip/PyQt5/QtWebKit/qwebhistoryinterface.sip
/usr/share/sip/PyQt5/QtWebKit/qwebkitglobal.sip
/usr/share/sip/PyQt5/QtWebKit/qwebpluginfactory.sip
/usr/share/sip/PyQt5/QtWebKit/qwebsecurityorigin.sip
/usr/share/sip/PyQt5/QtWebKit/qwebsettings.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/QtWebKitWidgetsmod.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/qgraphicswebview.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/qwebframe.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/qwebinspector.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/qwebpage.sip
/usr/share/sip/PyQt5/QtWebKitWidgets/qwebview.sip