'Try to guess whether a unicode query part is a path query.
Condition: separator precedes colon and the file exists.'

@classmethod
def is_path_query(cls, query_part):

    colon = query_part.find(':')
    if (colon != (-1)):
        query_part = query_part[:colon]
    return (((os.sep in query_part) or (os.altsep and (os.altsep in query_part))) and os.path.exists(syspath(normpath(query_part))))
