python查找文件中出现大多数正则表达式匹配的部分

I'm reading a file line per line and checking where a code section ends: a specific sequence of characters appears. This sequence could occur within the code section so i have to check the redundancy : how many times successive lines contains the sequence. with 10 successive occurences i should return the first line where the successive occurences started to detect the end of the code section.I'm reading a file line per line and checking w