python3 quick_ratio计算结果不稳定的解决方式

网上找不到，也许是大家都不用，个人遇到了，所以记录下解决方案

seq = difflib.SequenceMatcher(None)

seq是一个类，计算结果会存起来

当使用单例模式时，上一次计算结果会影响本次计算结果

重置为：

seq.fullbcount = None

代码：

import difflib
seq = difflib.SequenceMatcher(None)
str1 = "0603 5%"
def test():
    str1 = "0603 5%"
    str2 = "0603 5% 6.1x2.6"

    seq.a = str1
    seq.b = str2
    print(round(seq.quick_ratio(), 3), seq.a, seq.b)
    seq.b = "asdg d ef w5 121 51f35s"
    print(round(seq.quick_ratio(), 3), seq.a, seq.b)
    seq.fullbcount = None
    seq.b = "asdg d ef w5 121 51f35s"
    print(round(seq.quick_ratio(), 3), seq.a, seq.b)
test()

输出

0.636 0603 5% 0603 5% 6.1x2.6
0.467 0603 5% asdg d ef w5 121 51f35s
0.2 0603 5% asdg d ef w5 121 51f35s