(I don't know where to send a pull request, so I'm sending one here. If there is a proper way to send a pull request, please kindly inform me.)
`./kokoro/ubuntu/test.sh` requires python 2, but a simple tweak makes it work also for python 3:
```
diff --git a/test/hftest/hftest.py b/test/hftest/hftest.py
index 7834c4d..bf66bb2 100755
--- a/test/hftest/hftest.py
+++ b/test/hftest/hftest.py
@@ -258,7 +258,7 @@ def Main():
suite_xml.set("failures", str(failures_from_suite))
suites_xml.set("tests", str(tests_run))
suites_xml.set("failures", str(failures))
- with open(os.path.join(log, "sponge_log.xml"), "w") as f:
+ with open(os.path.join(log, "sponge_log.xml"), "wb") as f:
ET.ElementTree(suites_xml).write(
f, encoding='utf-8', xml_declaration=True)
# If none were run, this is probably a mistake.
```