Python Regex - Remove special characters but preserve apostraphes
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I am attempting to remove all special characters from some text, here is my regex:

    pattern = re.compile('[\W_]+', re.UNICODE)
    words = str(pattern.sub(' ', words))

Super simple, but unfortunately it is causing problems when using apostrophes (single quotes). For example, if I had the word "doesn't", this code is returning "doesn". 

Is there any way of adapting this regex so that it doesn't remove apostrophes in instances like this?