human
Solve the following python programming problem given the following code:
def url_converter(self, name) : 
    '
        Returns the custom URL converter for the given file name.
        ' 
    def converter(matchobj) : 
        '
            Converts the matched URL depending on the parent level (`..`)
            and returns the normalized and hashed URL using the url method
            of the storage.
            ' 
        (matched, url) = matchobj.groups () 
        if url.startswith (('#', 'http:', 'https:', 'data:')) : 
            return matched 
name_parts = name.split (os.sep) 
        url = posixpath.normpath (url) 
        url_parts = url.split ('/') 
        (parent_level, sub_level) = (url.count ('..'), url.count ('/')) 
        if url.startswith ('/') : 
            sub_level -= 1 
            url_parts = url_parts [1 :] 
if (parent_level or (not url.startswith ('/'))) : 
            (start, end) = ((parent_level + 1), parent_level) 
else : 
            if sub_level : 
                if (sub_level == 1) : 
                    parent_level -= 1 
(start, end) = (parent_level, (sub_level - 1)) 
else : 
                (start, end) = (1, (sub_level - 1)) 
joined_result = '/'.join ((name_parts [: (- start)] + url_parts [end :])) 
        hashed_url = self.url (unquote (joined_result), force = True) 
        return ('url("%s")' % unquote (hashed_url)) 
return self 

    
    

    Fix the buggy line: return self
assistant
#Here is Python code to fix the buggy line: return self
.

return def converter(