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Summary: As titled. Add comment for the rules for clarity.

Differential Revision: D55035875

Author: cicichen01

setup.cfg

@@ -1,6 +1,7 @@
 [flake8]
 # E203: black and flake8 disagree on whitespace before ':'
 # W503: black and flake8 disagree on how to place operators
+# E704: black and flake8 disagree on Multiple statements on one line (def)
 ignore = E203, W503, E704
 max-line-length = 88
 exclude =