fix corehq/ex-submodules/couchexport/tests/test_writers.py and use unicode sandwich
fix corehq/ex-submodules/couchexport/tests/test_writers.py and use unicode sandwich

dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq