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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 _decode_time_rotation_index(self, time_rot_index):
        ''' Return the time struct index to use for log rotation checks '''
        time_index_decode_table = {
            'year': 0,    'years': 0,    'tm_year': 0,
            'month': 1,   'months': 1,   'tm_mon': 1,
            'day': 2,     'days': 2,     'tm_mday': 2,
            'hour': 3,    'hours': 3,    'tm_hour': 3,
            'minute': 4,  'minutes': 4,  'tm_min': 4,
            'second': 5,  'seconds': 5,  'tm_sec': 5,
        }

        if time_rot_index not in time_index_decode_table.keys():
            raise ValueError('Invalid time option specified for log rotation')

        return time_index_decode_table[time_rot_index]