color_scheme.py 文件源码

def _pop_symbol_list(self, lists):
        symbol_lists = []
        for l in lists:
            mark = True
            for s in l:
                if s is not None and not isinstance(s, Symbol):
                    mark = False
                    break
            if mark:
                lists.remove(l)
                symbol_lists.append(l)
        if len(symbol_lists) == 1:
            return symbol_lists[0]
        elif len(symbol_lists) == 0:
            return []
        else:
            raise ValueError("Only one list of Symbols "
                             "can be given for a color scheme.")