If I am trying to backtest one of the example algos in the algorithm frame work page, I get below error.

Algorithm.Initialize() Error: During the algorithm initialization, the following exception has occurred: Loader.TryCreatePythonAlgorithm(): Unable to import python module ./cache/algorithm/main.pyc. AlgorithmPythonWrapper(): Please ensure that one class inherits from QCAlgorithm. in AlgorithmPythonWrapper.cs:line 136 Please ensure that one class inherits from QCAlgorithm. Stack Trace: During the algorithm initialization, the following exception has occurred: Loader.TryCreatePythonAlgorithm(): Unable to import python module ./cache/algorithm/main.pyc. AlgorithmPythonWrapper(): Please ensure that one class inherits from QCAlgorithm. in AlgorithmPythonWrapper.cs:line 136 Please ensure that one class inherits from QCAlgorithm. (Open Stacktrace)

 

What exactly am I missing?