Using Ubuntu 18.04. Say we have a file called `debug.log`. You can create a copy called `debug_BACKUP.log` with either of these commands:

```
cp debug.log debug_BACKUP.log
cp debug{,_BACKUP}.log

```

Alternatively, substitute `cp` with `mv` to rename the file.

Now suppose we have `debug1.log` and `debug2.log`. We would like to create copies called `debug1_BACKUP.log` and `debug2_BACKUP.log`. Is there a single command to achieve this?

When I tried either of the following:

```
cp debug*.log debug*_BACKUP.log
cp debug*{,_BACKUP}.log

```

the error is `cp: target 'debug*_BACKUP.log' is not a directory`.