code: def saveFormatFile(self, filename, format):
          
          ret = libxml2mod.xmlSaveFormatFile(filename, self._o, format)
          return ret
docs: Dump an XML document to a file. Will use compression if
            compiled in and enabled. If @filename is "-" the stdout
            file is used. If @format is set then the document will be
            indented on output. Note that @format = 1 provide node
            indenting only if xmlIndentTreeOutput = 1 or
             xmlKeepBlanksDefault(0) was called