第一行中span的作用？第二行为何返回none?
import re
print(re.match('www','www.runoob.com').span())
print(re.match('com','www.runoob.com'))
一头雾水
line = "Cats are smarter than dogs"
matchObj = re.match(r'(.*) are (.*?) .*', line, re.M | re.I)
if matchObj:
print "matchObj.group() : ", matchObj.group()
print "matchObj.group(1) : ", matchObj.group(1)
print "matchObj.group(2) : ", matchObj.group(2)
else:
print
"No match!!"
