唯一坐标转换问题

现在有一个二维坐标组成的数组，例如
[[0,7],[8,10],[12,19],[13,15],[2,9],[19,22],[25,27],[30,33]];

这些坐标可以按照以下规则进行转换，例如：

1.坐标之间可以组成连续的坐标，则这些坐标可以转化为一个坐标，
[0,7] & [8,10] -> [0,10]

2.坐标之间存在包含关系，则这些坐标可以转换为一个坐标，
[12,19] & [13,15] -> [12,19]

需要经过重新计算将数组内的坐标转换为唯一坐标（即 既不包含（或者被包含）其他坐标，也不能和其他坐标连续的坐标），例子里的坐标的转化结果为：
[[0,7],[8,10],[12,19],[13,15],[2,9],[19,22],[25,27],[30,33]]
->
[[0,10],[12,22],[25,27],[30,33]]

请写出转化算法：
def merge(list):

def by_rule_merge_ranges(list):
    merge_list = []
    def _merge(ranges):
        copy_ranges = copy.deepcopy(ranges)
        ranges_length = len(ranges)-1
        start_offset = copy_ranges[0][0]
        end_offset = copy_ranges[0][1]
        for j in range(ranges_length):
            if j < ranges_length:
                next_start_offset = ranges[j + 1][0]
                next_end_offset = ranges[j + 1][1]
                if start_offset <= (next_end_offset + 1) and start_offset >= next_start_offset and end_offset >= next_end_offset:
                    start_offset = next_start_offset
                    copy_ranges.remove(ranges[j+1])
                elif end_offset >= (next_start_offset - 1) and end_offset <= next_end_offset and start_offset <= next_start_offset:
                    end_offset = next_end_offset
                    copy_ranges.remove(ranges[j + 1])
                elif start_offset >= next_start_offset and end_offset <= next_end_offset:
                    start_offset = next_start_offset
                    end_offset = next_end_offset
                    copy_ranges.remove(ranges[j + 1])
                elif start_offset <= next_start_offset and end_offset >= next_end_offset:
                    copy_ranges.remove(ranges[j + 1])
        copy_ranges.remove(copy_ranges[0])
        merge_list.append({
            'startOffset': start_offset,
            'endOffset': end_offset,
            'count': 0
        })
        if len(copy_ranges) == 0:
            return 
        else:
            _merge(copy_ranges)
    _merge(list)
    return merge_list