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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convertToNative(self, aVal):
 """ Convert to native bool; interpret certain strings. """

        if aVal is None:
            return None
        if isinstance(aVal, bool): return aVal
        # otherwise interpret strings
        return str(aVal).lower() in ('1','on','yes','true')