Python match and replace, what I do wrong?

Question

I have reg exp for match some data (is it here ) and now I try to replace all matched data with single : characetr

test_str = u"THERE IS MY DATA"
p = re.compile(ur'[a-z]+([\n].*?<\/div>[\n ]+<div class="large-3 small-3 columns">[\n ]+)[a-z]+', re.M|re.I|re.SE) 
print re.sub(p, r':/1',test_str) 

I try it on few other way but it's not replace any or replace not only matched but whole pattern

Answer 1

1)It's backslash issue.
Use : print re.sub(p, r':\\1',test_str) not print re.sub(p, r':/1',test_str) .
2)You are replacing all the pattern with :\\1 , that means replace all the text with : followed by the first group in the regex.
To replace just the first group inside the text you should add two groups , before the first and after. I hope this will fix the issue:

test_str = u"THERE IS MY DATA" 
p = re.compile(ur'([a-z]+)([\n].*?<\/div>[\n ]+<div class="large-3 small-3 columns">[\n ]+)([a-z]+)', re.M|re.I|re.SE) 
print re.sub(p, r'\1:\2\3',test_str)