Python正则表达式实现截取成对括号的方法

strs = '1(2(3(4(5(67)6)7)8)9)0'
reg1 = re.compile('([()])?') #一对括号
reg2 = re.compile('([()]|([()]?)*)') #两对括号
reg3 = re.compile('([()]|([()]?|([()]|([()]?)*))*)') #三层

#匹配成对括号正则表达式
def getReg(self, count, bracket = '()'):
 leftBracket = bracket[0]
 rightBracket = bracket[1]
 count -= 1
 regBasic = leftBracket + '(?:[^' + leftBracket + rightBracket + '])*' + rightBracket
 if count < 0:
 regBasic = ''
 if count > 0:
 for i in xrange(count):
 tempNum = regBasic.rfind('*') - 1
 regBasic = regBasic[:tempNum] + "|" + regBasic + regBasic[tempNum:]
 return regBasic