code: def assist(self, project_path, source, position, filename):
          
          return self._call('assist', project_path, source, position, filename)
docs: Return completion match and list of completion proposals
  
          :param project_path: absolute project path
          :param source: unicode or byte string code source
          :param position: character or byte cursor position
          :param filename: absolute path of file with source code
          :returns: tuple (completion match, sorted list of proposals)