fixed errors and making flake pass

freqtrade/analyze.py

@@ -105,7 +105,7 @@ class Analyze(object):
         """
         return self.strategy.stoploss
 
-    def analyze_ticker(self, ticker_history: List[Dict]) -> DataFrame:
+    def analyze_ticker(self, ticker_history: List[Dict], pair: str) -> DataFrame:
         """
         Parses the given ticker history and returns a populated DataFrame
         add several TA indicators and buy signal to it

freqtrade/strategy/interface.py

@@ -6,7 +6,6 @@ import warnings
 from abc import ABC, abstractmethod
 from typing import Dict
 
-from abc import ABC
 from pandas import DataFrame
 
 
@@ -30,6 +29,7 @@ class IStrategy(ABC):
     # associated ticker interval
     ticker_interval: str
 
+    @abstractmethod
     def populate_indicators(self, dataframe: DataFrame) -> DataFrame:
         """
         Populate indicators that will be used in the Buy and Sell strategy
@@ -40,6 +40,7 @@ class IStrategy(ABC):
                       DeprecationWarning)
         return dataframe
 
+    @abstractmethod
     def populate_buy_trend(self, dataframe: DataFrame) -> DataFrame:
         """
         Based on TA indicators, populates the buy signal for the given dataframe
@@ -51,6 +52,7 @@ class IStrategy(ABC):
         dataframe.loc[(), 'buy'] = 0
         return dataframe
 
+    @abstractmethod
     def populate_sell_trend(self, dataframe: DataFrame) -> DataFrame:
         """
         Based on TA indicators, populates the sell signal for the given dataframe