match a paragraph starts with some letter

I have a file that contains paragraphs starting with AB, I wanted to get all these paragraphs, I used the following code, but it returns nothing:

import 开发者_开发问答re
paragraphs = re.findall(r'AB[.\n]+AD',text) #AD is the beginning of the next paragraph

Any idea why did not this work?

Thanks

Try:

re.findall(r'AB.+?(?=AD)', text, re.DOTALL)

The re.DOTALL flag will let the dot cover everything included the newlines. And (?=AD) will match everything up to the last character before AD, but will not include AD into the matched string.

You can then rstrip() the resulting strings to remove all newlines from the end.

from the python re module documentation:

[] 
    Used to indicate a set of characters. Characters can be listed individually, 
    or a range of characters can be indicated by giving two characters and 
    separating them by a '-'. Special characters are not active inside sets.

this means that . inside the brackets matches a dot, and not any character as it would anywhere else in a regexp.