Add whitespace after , to fix lint issue kernc#356

Author: zlpatel

backtesting/_plotting.py

@@ -391,9 +391,9 @@ def _plot_pl_section():
         returns_short = np.where(trades['Size'] < 0, trades['ReturnPct'], np.nan)
         size = trades['Size'].abs()
         size = np.interp(size, (size.min(), size.max()), (8, 20))
-        ohlcv_index_trade_close_arr = np.empty(source.data['index'][-1]+1,dtype=float)
+        ohlcv_index_trade_close_arr = np.empty(source.data['index'][-1]+1, dtype=float)
         ohlcv_index_trade_close_arr[trade_source.data['index']] = trades['ReturnPct']
-        source.add(ohlcv_index_trade_close_arr,'return_pct')
+        source.add(ohlcv_index_trade_close_arr, 'return_pct')
         trade_source.add(returns_long, 'returns_long')
         trade_source.add(returns_short, 'returns_short')
         trade_source.add(size, 'marker_size')