/usr/lib/python3/dist-packages/Cython/Includes/libc/ is in cython3 0.25.2-1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/python3/dist-packages/Cython/Includes/libc/__init__.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/errno.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/float.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/limits.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/locale.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/math.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/setjmp.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/signal.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/stddef.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/stdint.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/stdio.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/stdlib.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/string.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libc/time.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/__init__.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/algorithm.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/cast.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/complex.pxd
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/usr/lib/python3/dist-packages/Cython/Includes/libcpp/iterator.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/limits.pxd
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/usr/lib/python3/dist-packages/Cython/Includes/libcpp/memory.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/pair.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/queue.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/set.pxd
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/usr/lib/python3/dist-packages/Cython/Includes/libcpp/unordered_map.pxd
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/usr/lib/python3/dist-packages/Cython/Includes/libcpp/utility.pxd
/usr/lib/python3/dist-packages/Cython/Includes/libcpp/vector.pxd