/usr/share/sip/PyQt5/QtDesigner/ is in pyqt5-dev 5.10.1+dfsg-1ubuntu2.
This file is owned by root:root, with mode 0o755.
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/usr/share/sip/PyQt5/QtDesigner/QtDesignermod.sip
/usr/share/sip/PyQt5/QtDesigner/abstractactioneditor.sip
/usr/share/sip/PyQt5/QtDesigner/abstractformbuilder.sip
/usr/share/sip/PyQt5/QtDesigner/abstractformeditor.sip
/usr/share/sip/PyQt5/QtDesigner/abstractformwindow.sip
/usr/share/sip/PyQt5/QtDesigner/abstractformwindowcursor.sip
/usr/share/sip/PyQt5/QtDesigner/abstractformwindowmanager.sip
/usr/share/sip/PyQt5/QtDesigner/abstractobjectinspector.sip
/usr/share/sip/PyQt5/QtDesigner/abstractpropertyeditor.sip
/usr/share/sip/PyQt5/QtDesigner/abstractwidgetbox.sip
/usr/share/sip/PyQt5/QtDesigner/container.sip
/usr/share/sip/PyQt5/QtDesigner/customwidget.sip
/usr/share/sip/PyQt5/QtDesigner/default_extensionfactory.sip
/usr/share/sip/PyQt5/QtDesigner/extension.sip
/usr/share/sip/PyQt5/QtDesigner/formbuilder.sip
/usr/share/sip/PyQt5/QtDesigner/membersheet.sip
/usr/share/sip/PyQt5/QtDesigner/propertysheet.sip
/usr/share/sip/PyQt5/QtDesigner/qextensionmanager.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignercontainerextension.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignercustomwidgetcollectionplugin.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignercustomwidgetplugin.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignermembersheetextension.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignerpropertysheetextension.sip
/usr/share/sip/PyQt5/QtDesigner/qpydesignertaskmenuextension.sip
/usr/share/sip/PyQt5/QtDesigner/taskmenu.sip