Error While Executing Momentum-based Tactical Asset Allocation Algorithm

English Programming/Scripting
1

Hi,

I am trying to execute this code-

class MomentumBasedTacticalAllocation(QCAlgorithm):

    def Initialize(self):
        self.SetStartDate(2007, 8, 1)  # Set Start Date
        self.SetEndDate(2010, 8, 1)  # Set End Date
        
        #1. Subscribe to SPY -- S&P 500 Index ETF -- using daily resolution
        
        #2. Subscribe to BND -- Vanguard Total Bond Market ETF -- using daily resolution
        
        #3. Set strategy cash to $3000
        
    def OnData(self, data):
        pass

Basically this [Python] ------Link removed because commercial site------- code from the module of 7 is a class definition for a momentum-based tactical asset allocation algorithm for use in the QuantConnect Algorithm Trading Engine.

When I execute the code, it is showing error- exercise failed, please try again.

Can anyone please solve this error.

Thanks in advance.
James