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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 all_valid_time_intervals():
        '''
        Helper method to return all possible valid time intervals for data
        stored by Perfherder
        '''
        return [PerformanceTimeInterval.DAY,
                PerformanceTimeInterval.WEEK,
                PerformanceTimeInterval.TWO_WEEKS,
                PerformanceTimeInterval.SIXTY_DAYS,
                PerformanceTimeInterval.NINETY_DAYS,
                PerformanceTimeInterval.ONE_YEAR]