我做了一个python脚本来从心脏病学报告中提取信息（作为txt文件），看起来像这样：

Cardiac report: Complete

Hospital  Ultrasound Laboratory

----------

Name Test Test Birthdate  Patient 123 Gender  Height  Weight  BSA  BP 

Date 01/01/0001 Tape  Sonographer  Ref. Doc.  Physician 

----------

2D 

AVC 351 ms Peak SL Dispersion Full  67  ms G peak SL Full(APLAX)    -16 % G
peak SL Full(A4C)   -13 % G peak SL Full(A2C)   -16 % G peak SL
Full(Avg)   -15 % BA PSSL Full  -8  % BI PSSL Full  -9  % MA PSSL Full  -10 %
MI PSSL Full    -20 % AA PSSL Full  -21 % AI PSSL Full  -31 % BAS PSSL
Full    -11 % BP PSSL Full  -6  % MAS PSSL Full -22 % MP PSSL Full  -6  %

正如你所看到的，我在列表中显式地搜索特定的“键”，然后使用正则表达式搜索键+值的数字行，然后将匹配的行放入字典中，将它们分解成键-值对

import re

keys = ['AVC', 'Peak SL Dispersion Full', 'G peak SL Full(A4C)',  'G peak SL Full(Avg)', 'G peak SL Full(APLAX)', 'BA PSSL Full', 'BI PSSL Full', 'MA PSSL Full', 'MP PSSL Full']

results = {}
with open('report1.txt') as f:
    content = f.read()
    for key in keys:
        match = re.search(key + r'\s+([\d.-]+)', content)
        if match:
            results[key] = float(match.group(1))

print(results)

由于未知的原因，我不能re.search的关键字有括号，如'G peak SL Full(A4C)', 'G peak SL Full(Avg)', 'G peak SL Full(APLAX)'
当我从txt文件中的键中删除（）时，像这样的代码'G peak SL FullA4C', 'G peak SL FullAvg', 'G peak SL FullAPLAX'，它们神奇地被搜索并插入到最终的字典中。
这是什么原因呢？