Python正则表达式将外部文本与标签之间的文本结合在一起

Question

我有以下字符串（阶段1）：

(Undergraduate level  <A HREF="blah=">PHYS 218</A> Minimum Grade of D) and (Undergraduate level  <A HREF="blah">MATH 152</A> Minimum Grade of D or Undergraduate level  <A HREF="/blah=">MATH 172</A> Minimum Grade of D or Undergraduate level  <A HREF="blah">MATH 251</A> Minimum Grade of D)

从这里我进入（阶段2）：

(Undergraduate level PHYS 218 Minimum Grade of D) and (Undergraduate level MATH 152 Minimum Grade of D or Undergraduate level MATH 172 Minimum Grade of D or Undergraduate level MATH 251 Minimum Grade of D)

然后最终我想要的是（阶段3）：

(PHYS 218) and (MATH 152 or MATH 172 or MATH 251)

目前，我这样做的方式太可怕了。

我采用阶段1的字符串，完全删除所有a标签，然后合并剩余的文本。

然后，我从a标签中获取课程编号，并将其放入上述步骤的字符串中，以进入第二阶段。

然后，我在第二阶段中查找课程，删除该课程左右两边的所有内容，直到我碰到( ， ) or ， and为止。

有什么方法可以使用正则表达式或其他方法完全做到这一点？ 谢谢。

Answer 1

x="""(Undergraduate level  <A HREF="blah=">PHYS 218</A> Minimum Grade of D) and (Undergraduate level  <A HREF="blah">MATH 152</A> Minimum Grade of D or Undergraduate level  <A HREF="/blah=">MATH 172</A> Minimum Grade of D or Undergraduate level  <A HREF="blah">MATH 251</A> Minimum Grade of D)"""
import re
print re.sub(r"<[^>]*>\s*|Undergraduate level\s*|Minimum Grade of [A-Z]+","",x)

如果格式始终是固定的并且不会有太大变化，则可以使用re.sub 。

参见演示。

https://regex101.com/r/hF7zZ1/2

编辑：

如果文本更改，请尝试此

x="""(Undergraduate level  <A HREF="blah=">PHYS 218</A> Minimum Grade of D) and (Undergraduate level  <A HREF="blah">MATH 152</A> Minimum Grade of D or Undergraduate level  <A HREF="/blah=">MATH 172</A> Minimum Grade of D or Undergraduate level  <A HREF="blah">MATH 251</A> Minimum Grade of D)"""
import re
print "".join(re.findall(r"(\(|\)|\s*or\s*|\s*and\s*|(?<=>)[^<]*(?=<\/A>))",x))