I wrote the following script in the test.sh:

```
#!/bin/sh
compare() { 
if [ $1 != root ]; then 
echo "Fail" >> CAT1.txt 
fi 
}
awk -F: '$4 == 0' /etc/passwd | cut -d: f1 | xargs -n1 -i bash -c 'compare "$@"' _

```

when I execute this scripts, get the following error:

```
_: compare: command not found

```