Revert several undesired changes

freqtrade/exchange/exchange.py

@@ -383,8 +383,8 @@ class Exchange:
         Ensures that Configured mode aligns to
         """
         return (
-            market.get('quote') is not None
-            and market.get('base') is not None
+            market.get('quote', None) is not None
+            and market.get('base', None) is not None
             and (self.precisionMode != TICK_SIZE
                  # Too low precision will falsify calculations
                  or market.get('precision', {}).get('price') > 1e-11)
@@ -1599,7 +1599,7 @@ class Exchange:
     def get_fee(self, symbol: str, type: str = '', side: str = '', amount: float = 1,
                 price: float = 1, taker_or_maker: str = 'maker') -> float:
         try:
-            if self._config['dry_run'] and self._config.get('fee') is not None:
+            if self._config['dry_run'] and self._config.get('fee', None) is not None:
                 return self._config['fee']
             # validate that markets are loaded before trying to get fee
             if self._api.markets is None or len(self._api.markets) == 0:
@@ -1660,7 +1660,7 @@ class Exchange:
 
                 fee_to_quote_rate = safe_value_fallback2(tick, tick, 'last', 'ask')
             except ExchangeError:
-                fee_to_quote_rate = self._config['exchange'].get('unknown_fee_rate')
+                fee_to_quote_rate = self._config['exchange'].get('unknown_fee_rate', None)
                 if not fee_to_quote_rate:
                     return None
             return round((self._contracts_to_amount(

freqtrade/freqtradebot.py

@@ -855,7 +855,7 @@ class FreqtradeBot(LoggingMixin):
             'order_type': order_type,
             'stake_amount': trade.stake_amount,
             'stake_currency': self.config['stake_currency'],
-            'fiat_currency': self.config.get('fiat_display_currency'),
+            'fiat_currency': self.config.get('fiat_display_currency', None),
             'amount': safe_value_fallback(order, 'filled', 'amount') or trade.amount,
             'open_date': trade.open_date or datetime.utcnow(),
             'current_rate': current_rate,
@@ -884,7 +884,7 @@ class FreqtradeBot(LoggingMixin):
             'order_type': order_type,
             'stake_amount': trade.stake_amount,
             'stake_currency': self.config['stake_currency'],
-            'fiat_currency': self.config.get('fiat_display_currency'),
+            'fiat_currency': self.config.get('fiat_display_currency', None),
             'amount': trade.amount,
             'open_date': trade.open_date,
             'current_rate': current_rate,
@@ -1590,7 +1590,7 @@ class FreqtradeBot(LoggingMixin):
             'open_date': trade.open_date,
             'close_date': trade.close_date or datetime.now(timezone.utc),
             'stake_currency': self.config['stake_currency'],
-            'fiat_currency': self.config.get('fiat_display_currency'),
+            'fiat_currency': self.config.get('fiat_display_currency', None),
             'reason': reason,
         }
 

freqtrade/optimize/backtesting.py

@@ -123,7 +123,7 @@ class Backtesting:
         if len(self.pairlists.whitelist) == 0:
             raise OperationalException("No pair in whitelist.")
 
-        if config.get('fee') is not None:
+        if config.get('fee', None) is not None:
             self.fee = config['fee']
         else:
             self.fee = self.exchange.get_fee(symbol=self.pairlists.whitelist[0])

freqtrade/plugins/pairlist/PriceFilter.py

@@ -70,7 +70,7 @@ class PriceFilter(IPairList):
         :param ticker: ticker dict as returned from ccxt.fetch_tickers()
         :return: True if the pair can stay, false if it should be removed
         """
-        if ticker.get('last') is None or ticker.get('last') == 0:
+        if ticker.get('last', None) is None or ticker.get('last') == 0:
             self.log_once(f"Removed {pair} from whitelist, because "
                           "ticker['last'] is empty (Usually no trade in the last 24h).",
                           logger.info)