def assist(self, project_path, source, position, filename):
        """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)
        """
        return self._call('assist', project_path, source, position, filename)
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)