code: def init (self, base_ref, base_url, parent_url, recursion_level,
                aggregate, line, column, page, name, url_encoding, extern):
          
          super(FileUrl, self).init(base_ref, base_url, parent_url,
           recursion_level, aggregate, line, column, page, name, url_encoding, extern)
          self.scheme = u'file'
docs: Initialize the scheme.