def sanitizefilename(unsanitizedfn,debug=False):
        #make safe for a filename
        if debug:
                print unsanitizedfn
        #remove disallowed characters
        filenamesubbed = re.sub('[^A-Za-z0-9 \.]+', '-', unsanitizedfn)
        if debug:
                print filenamesubbed
        #remove duplicate underscores and spaces
        filenamesubbed = re.sub("_+", "_", filenamesubbed)
        if debug:
                print filenamesubbed
        #make sure first and last char arent spacees
        filenametrimmed = filenamesubbed.strip()
        if debug:
                print filenametrimmed
        return filenametrimmed