Sequence 'seq_3': Invalid character 'U' at location 9.

Sequence 'seq_3': Invalid character 'U' at location 42.

Sequence 'seq_3': Invalid character 'O' at location 45.

Sequence 'seq_3': Invalid character 'U' at location 60.

Sequence 'seq_3': Invalid character 'O' at location 63.

Sequence 'seq_3': Invalid character 'U' at location 90.

Sequence 'seq_3': Invalid character 'U' at location 120.

Sequence 'seq_3': Invalid character 'O' at location 135.

Sequence 'seq_3': Invalid character 'O' at location 153.

Sequence 'seq_3': Invalid character 'U' at location 210.

Sequence 'seq_3': Invalid character 'U' at location 273.

Sequence 'seq_3': Invalid character 'U' at location 279.

Sequence 'seq_3': Invalid character 'U' at location 294.

Sequence 'seq_3': Invalid character 'O' at location 297.

Sequence 'seq_3': Invalid character 'U' at location 312.

Sequence 'seq_3': Invalid character 'O' at location 324.

Sequence 'seq_3': Invalid character 'U' at location 333.

……

……

问题表现：

只针对字母 U 和O 提示错误，其他字母不提示错误。

原因分析：

解决方法：