Changed syntax in testutils.py that is introduced in 3.6 to a backwards compatible version.
@@ -14,7 +14,7 @@ def assert_raises(exc_type, expr, msg=None):
except exc_type:
pass
else:
- failmsg = f'{exc_type.__name__} was not raised'
+ failmsg = '%s was not raised' % exc_type.__name__
if msg is not None:
- failmsg += f': {msg}'
+ failmsg += ': %s' % msg
assert False, failmsg
