diff --git a/freqtrade/exceptions.py b/freqtrade/exceptions.py
index 056be8720..6b0039a3f 100644
--- a/freqtrade/exceptions.py
+++ b/freqtrade/exceptions.py
@@ -1,5 +1,3 @@
-
-
 class FreqtradeException(Exception):
     """
     Freqtrade base exception. Handled at the outermost level.
diff --git a/freqtrade/strategy/hyper.py b/freqtrade/strategy/hyper.py
index eaf41263a..278954bb2 100644
--- a/freqtrade/strategy/hyper.py
+++ b/freqtrade/strategy/hyper.py
@@ -292,7 +292,7 @@ class BooleanParameter(CategoricalParameter):
                          load=load, **kwargs)
 
 
-class HyperStrategyMixin(object):
+class HyperStrategyMixin:
     """
     A helper base class which allows HyperOptAuto class to reuse implementations of buy/sell
      strategy logic.
diff --git a/freqtrade/strategy/interface.py b/freqtrade/strategy/interface.py
index d11097ed2..47a226f16 100644
--- a/freqtrade/strategy/interface.py
+++ b/freqtrade/strategy/interface.py
@@ -30,7 +30,7 @@ logger = logging.getLogger(__name__)
 CUSTOM_SELL_MAX_LENGTH = 64
 
 
-class SellCheckTuple(object):
+class SellCheckTuple:
     """
     NamedTuple for Sell type + reason
     """
diff --git a/freqtrade/wallets.py b/freqtrade/wallets.py
index 1a124d1bb..d10847099 100644
--- a/freqtrade/wallets.py
+++ b/freqtrade/wallets.py
@@ -73,7 +73,7 @@ class Wallets:
             tot_profit = Trade.get_total_closed_profit()
         else:
             tot_profit = LocalTrade.total_profit
-        tot_in_trades = sum([trade.stake_amount for trade in open_trades])
+        tot_in_trades = sum(trade.stake_amount for trade in open_trades)
 
         current_stake = self.start_cap + tot_profit - tot_in_trades
         _wallets[self._config['stake_currency']] = Wallet(
diff --git a/scripts/rest_client.py b/scripts/rest_client.py
index ccb34d81f..b1234d329 100755
--- a/scripts/rest_client.py
+++ b/scripts/rest_client.py
@@ -39,7 +39,7 @@ class FtRestClient():
     def _call(self, method, apipath, params: dict = None, data=None, files=None):
 
         if str(method).upper() not in ('GET', 'POST', 'PUT', 'DELETE'):
-            raise ValueError('invalid method <{0}>'.format(method))
+            raise ValueError(f'invalid method <{method}>')
         basepath = f"{self._serverurl}/api/v1/{apipath}"
 
         hd = {"Accept": "application/json",
@@ -124,7 +124,7 @@ class FtRestClient():
         :param lock_id: ID for the lock to delete
         :return: json object
         """
-        return self._delete("locks/{}".format(lock_id))
+        return self._delete(f"locks/{lock_id}")
 
     def daily(self, days=None):
         """Return the profits for each day, and amount of trades.
@@ -220,7 +220,7 @@ class FtRestClient():
         :param trade_id: Specify which trade to get.
         :return: json object
         """
-        return self._get("trade/{}".format(trade_id))
+        return self._get(f"trade/{trade_id}")
 
     def delete_trade(self, trade_id):
         """Delete trade from the database.
@@ -229,7 +229,7 @@ class FtRestClient():
         :param trade_id: Deletes the trade with this ID from the database.
         :return: json object
         """
-        return self._delete("trades/{}".format(trade_id))
+        return self._delete(f"trades/{trade_id}")
 
     def whitelist(self):
         """Show the current whitelist.
diff --git a/tests/test_plotting.py b/tests/test_plotting.py
index 51301a464..8cbe7f863 100644
--- a/tests/test_plotting.py
+++ b/tests/test_plotting.py
@@ -1,4 +1,3 @@
-
 from copy import deepcopy
 from pathlib import Path
 from unittest.mock import MagicMock