已知包含多个车牌号的字符串:s="AZ7Y90,,B78T11,,HI89Op,K781Ui,AL009H,C88k8P,,nP8291G,m8H88H,DDS822,,QMK782,PYJ212"删除多余的逗号，将所有字母改写成大写字母格式将修改后的事

以下是 Python 代码实现：

s = "AZ7Y90,,B78T11,,HI89Op,K781Ui,AL009H,C88k8P,,nP8291G,m8H88H,DDS822,,QMK782,PYJ212"

# 删除多余的逗号
s = s.replace(",,", ",")

# 将所有字母改写成大写字母格式
s = s.upper()

# 输出修改后的字符串
print(s)

输出结果为：

AZ7Y90,B78T11,HI89OP,K781UI,AL009H,C88K8P,NP8291G,M8H88H,DDS822,QMK782,PYJ212