diff --git a/freqtrade/arguments.py b/freqtrade/arguments.py
index d623b7d7a..f6fb2dedb 100644
--- a/freqtrade/arguments.py
+++ b/freqtrade/arguments.py
@@ -517,7 +517,8 @@ class Arguments(object):
         )
         parser.add_argument(
             '--trade-source',
-            help='Specify the source for trades (Can be DB or file (backtest file)) Default: %(default)s',
+            help='Specify the source for trades (Can be DB or file (backtest file)) '
+                 'Default: %(default)s',
             dest='trade_source',
             default="file",
             choices=["DB", "file"]
diff --git a/scripts/plot_dataframe.py b/scripts/plot_dataframe.py
index 828373cb2..e5cc6ef89 100755
--- a/scripts/plot_dataframe.py
+++ b/scripts/plot_dataframe.py
@@ -124,7 +124,6 @@ def analyse_and_plot_pairs(config: Dict[str, Any]):
         tickers = {}
         tickers[pair] = data
         dataframe = generate_dataframe(strategy, tickers, pair)
-        trades = None
         if config["trade_source"] == "DB":
             trades = load_trades_from_db(config["db_url"])
         elif config["trade_source"] == "file":