diff --git a/tools/tests.sh b/tools/tests.sh
index f9b63b6cd..1e189760a 100755
--- a/tools/tests.sh
+++ b/tools/tests.sh
@@ -5,6 +5,9 @@
 # tools/tests.sh decks # test only test_decks.py
 # coverage=1 tools/tests.sh # run with coverage test
 
+BIN="$(cd "`dirname "$0"`"; pwd)"
+export PYTHONPATH=${BIN}/..:${PYTHONPATH}
+
 dir=.
 
 if [ x$1 = x ]; then