Blog_basic_resub.py

str1 = "ababcdcd cdbacdba abcdabcd"

import re

str2 = re.sub("a","1",str1)
print(str2)
#1b1bcdcd cdb1cdb1 1bcd1bcd

print(re.sub("a","1",str1,4))
#1b1bcdcd cdb1cdb1 abcdabcd

print(re.sub("[a-c]","x",str1))
#xxxxxdxd xdxxxdxx xxxdxxxd

print(re.sub("[a-b]+c","z",str1))
#zdcd cdzdba zdzd