/usr/share/pyshared/zope/structuredtext/regressions/ is in python-zope.structuredtext 3.5.1-0ubuntu3.
This file is owned by root:root, with mode 0o755.
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/usr/share/pyshared/zope/structuredtext/regressions/Acquisition.ref
/usr/share/pyshared/zope/structuredtext/regressions/Acquisition.stx
/usr/share/pyshared/zope/structuredtext/regressions/ExtensionClass.ref
/usr/share/pyshared/zope/structuredtext/regressions/ExtensionClass.stx
/usr/share/pyshared/zope/structuredtext/regressions/InnerLinks.ref
/usr/share/pyshared/zope/structuredtext/regressions/InnerLinks.stx
/usr/share/pyshared/zope/structuredtext/regressions/Links.ref
/usr/share/pyshared/zope/structuredtext/regressions/Links.stx
/usr/share/pyshared/zope/structuredtext/regressions/MultiMapping.ref
/usr/share/pyshared/zope/structuredtext/regressions/MultiMapping.stx
/usr/share/pyshared/zope/structuredtext/regressions/examples.ref
/usr/share/pyshared/zope/structuredtext/regressions/examples.stx
/usr/share/pyshared/zope/structuredtext/regressions/examples1.ref
/usr/share/pyshared/zope/structuredtext/regressions/examples1.stx
/usr/share/pyshared/zope/structuredtext/regressions/index.ref
/usr/share/pyshared/zope/structuredtext/regressions/index.stx
/usr/share/pyshared/zope/structuredtext/regressions/table.ref
/usr/share/pyshared/zope/structuredtext/regressions/table.stx