Satisfy linter.

freqtrade/pairlist/PerformanceFilter.py

@@ -12,6 +12,7 @@ from freqtrade.persistence import Trade
 
 logger = logging.getLogger(__name__)
 
+
 class PerformanceFilter(IPairList):
 
     def __init__(self, exchange, pairlistmanager,
@@ -19,7 +20,6 @@ class PerformanceFilter(IPairList):
                  pairlist_pos: int) -> None:
         super().__init__(exchange, pairlistmanager, config, pairlistconfig, pairlist_pos)
 
-
     @property
     def needstickers(self) -> bool:
         """
@@ -46,11 +46,11 @@ class PerformanceFilter(IPairList):
         # Get the trading performance for pairs from database
         perf = pd.DataFrame(Trade.get_overall_performance())
         # get pairlist from performance dataframe values
-        list_df = pd.DataFrame({'pair':pairlist})
+        list_df = pd.DataFrame({'pair': pairlist})
         # set initial value for pairs with no trades to 0
         # and sort the list using performance and count
         sorted_df = list_df.join(perf.set_index('pair'), on='pair')\
             .fillna(0).sort_values(by=['profit', 'count'], ascending=False)
         pairlist = sorted_df['pair'].tolist()
 
-        return pairlist
+        return pairlist