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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 execute(self, return_results=True):
        '''
        Executes the query and attempts to create model objects from results.
        '''
        if self.results:
            return self.results if return_results else None

        self.execute_raw()

        if self._raw_results_only:
            self.results = self.raw_results
        else:
            self.map_results()

        if return_results:
            return self.results