CLN: Update files (as per #36450) to Python 3.7+ syntax#36457

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jreback merged 1 commit intopandas-dev:masterfrom

ahgamut:style-py37

Sep 18, 2020

Commits on Sep 18, 2020

CLN: Update files (as per #36450) to Python 3.7+ syntax
ahgamut
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