Answers for "re.compile in python"

python replace regex

import re
s = "Example String"
replaced = re.sub('[ES]', 'a', s)
print replaced 
# will print 'axample atring'

python re compile

import re
#	Compile a regular expression pattern into a regular expression object, which can be used for matching using its match(), search() and other methods, described below.

prog = re.compile(pattern)
result = prog.match(string)

#	is equivalent to

result = re.match(pattern, string)

re python3

import re
>>> m = re.search('(?<=abc)def', 'abcdef')
>>> m.group(0)
'def'