Upgrade yapf to 0.20.0
Upgrade yapf version to 0.20.0 and reformat Python files.
diff --git a/tools/debug/core/error_ref_leak.py b/tools/debug/core/error_ref_leak.py
index 7806338..7e206c2 100644
--- a/tools/debug/core/error_ref_leak.py
+++ b/tools/debug/core/error_ref_leak.py
@@ -39,7 +39,7 @@
elif line[0] == "realloc":
errs.remove(line[1])
errs.append(line[3])
- # explicitly look for the last dereference
+ # explicitly look for the last dereference
elif line[1] == "1" and line[3] == "0":
assert (err in errs)
errs.remove(err)