HI Everyone! I am very new to QuantConnect and having problems with my first algorithm.

I get the error: "BacktestingRealTimeHandler.Run(): There was an error in a scheduled event SPY: EveryDay: SPY: 20 min after MarketOpen. The error was TypeError : No method matches given arguments for History"  when I try to run the following code:
 

import numpy as np class QuantumModulatedPrism(QCAlgorithm): def Initialize(self): self.SetCash(100000) self.SetStartDate(2019,9,1) self.SetEndDate(2020,12,1) self.symbol = self.AddEquity("SPY", Resolution.Daily).Symbol self.Debug(self.symbol) self.Log(self.symbol) self.lookback=20 self.ceiling,self.floor=30,10 self.initialStopRisk=0.98 self.trailingStopRisk=0.9 self.Schedule.On(self.DateRules.EveryDay(self.symbol),\ self.TimeRules.AfterMarketOpen(self.symbol,20),\ Action(self.EveryMarketOpen)) def OnData(self, data): self.Plot("Data Cahart", self.symbol, self.Securities[self.symbol].Close) def EveryMarketOpen(self): close=self.History(self.symbol, 31, Resolution.Daily)["close"] todayvol = np.std(close[1:31]) yesterdayvol=np.std(close[0:30]) deltavol = (todayvol-yesterdayvol)/todayvol self.lookback = self.lookback*(1+deltavol) if self.lookback>self.ceiling: self.lookback = self.ceiling elif self.lookback<self.floor: self.lookback=self.floor self.high = self.History(self.symbol, self.lookback, Resolution.Daily)["high"] if not self.Securities[self.symbol].Invested and \ self.Securities[self.symbol].Close >= max(self.high[:-1]): self.SetHoldings(self.symbol, 1) self.brakeoutlvl = max(self.high[:-1]) self.highestPrice = self.breakoulvl if self.Securities[self.symbol].Invested: if not self.Transactions.GetOpenOrders(self.symbol): self.stopMarketTicket= self.StopMarketOrder(self.symbol, \ -self.Protfolio[self.symbol].Quantity, \ self.initialStopRisk*self.breakoutlvl) if self.Securities[self.symbol].Close>self.highestPrice and \ self.initalStopRisk*self.breakoutlvl < self.Securities[self.symbol].Close*self.trailingStopRisk: self.highestPrice=self.Securities[self.symbol].Close updateFields=UpdateOrderFields() updateFields.StopPrice=self.Securities[self.symbol].Close*self.trailingStopRisk self.stopMarketTicket.Update(updateFields) self.Debug(updateFields.StopPrice) self.Plot("Data Chart", "Stop Price", self.stopMarketTicket.Get(OrderField.StopPrice))

I get the error when the scheduler is executed, but I have no clue why do I get it. 
Thank you in advance for your help and support!