CLN - pep8 adherence

Author: sds9995

pandas/tests/arithmetic/test_period.py

@@ -1099,10 +1099,8 @@ class TestPeriodArithmetic(object):
         (pd.offsets.YearEnd, 1),
     ])
     def test_period_diff(self, freq, expected):
-        #GH 23878
+        # GH 23878
         for i in range(1, 4):
             p1 = pd.Period('19910905', freq=freq(i))
             p2 = pd.Period('19920406', freq=freq(i))
             assert (p2 - p1) == freq(expected)
-
-