/usr/lib/python2.7/dist-packages/sage/structure/ is in sagemath-common 8.1-7ubuntu1.
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/usr/lib/python2.7/dist-packages/sage/structure/__init__.py
/usr/lib/python2.7/dist-packages/sage/structure/all.py
/usr/lib/python2.7/dist-packages/sage/structure/category_object.pxd
/usr/lib/python2.7/dist-packages/sage/structure/coerce.pxd
/usr/lib/python2.7/dist-packages/sage/structure/coerce_actions.pxd
/usr/lib/python2.7/dist-packages/sage/structure/coerce_dict.pxd
/usr/lib/python2.7/dist-packages/sage/structure/coerce_exceptions.py
/usr/lib/python2.7/dist-packages/sage/structure/coerce_maps.pxd
/usr/lib/python2.7/dist-packages/sage/structure/debug_options.pxd
/usr/lib/python2.7/dist-packages/sage/structure/dynamic_class.py
/usr/lib/python2.7/dist-packages/sage/structure/element.pxd
/usr/lib/python2.7/dist-packages/sage/structure/element_wrapper.pxd
/usr/lib/python2.7/dist-packages/sage/structure/factorization.py
/usr/lib/python2.7/dist-packages/sage/structure/factorization_integer.py
/usr/lib/python2.7/dist-packages/sage/structure/formal_sum.py
/usr/lib/python2.7/dist-packages/sage/structure/gens_py.py
/usr/lib/python2.7/dist-packages/sage/structure/global_options.py
/usr/lib/python2.7/dist-packages/sage/structure/graphics_file.py
/usr/lib/python2.7/dist-packages/sage/structure/indexed_generators.py
/usr/lib/python2.7/dist-packages/sage/structure/list_clone.pxd
/usr/lib/python2.7/dist-packages/sage/structure/list_clone_timings.py
/usr/lib/python2.7/dist-packages/sage/structure/mutability.pxd
/usr/lib/python2.7/dist-packages/sage/structure/nonexact.py
/usr/lib/python2.7/dist-packages/sage/structure/parent.pxd
/usr/lib/python2.7/dist-packages/sage/structure/parent_base.pxd
/usr/lib/python2.7/dist-packages/sage/structure/parent_gens.pxd
/usr/lib/python2.7/dist-packages/sage/structure/parent_old.pxd
/usr/lib/python2.7/dist-packages/sage/structure/proof/
/usr/lib/python2.7/dist-packages/sage/structure/proof/__init__.py
/usr/lib/python2.7/dist-packages/sage/structure/proof/all.py
/usr/lib/python2.7/dist-packages/sage/structure/proof/proof.py
/usr/lib/python2.7/dist-packages/sage/structure/richcmp.pxd
/usr/lib/python2.7/dist-packages/sage/structure/sage_object.pxd
/usr/lib/python2.7/dist-packages/sage/structure/sequence.py
/usr/lib/python2.7/dist-packages/sage/structure/set_factories.py
/usr/lib/python2.7/dist-packages/sage/structure/set_factories_example.py
/usr/lib/python2.7/dist-packages/sage/structure/test_factory.py
/usr/lib/python2.7/dist-packages/sage/structure/unique_representation.py