Fix imports
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index 6e4a149..a4aa206 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -31,6 +31,7 @@
 """Run tests in parallel."""
 
 import argparse
+import ast
 import glob
 import hashlib
 import itertools