I have 3 arrays that is already defined:

```
array1[:,:,:]
array2[:,:,:]
array3[:,:,:]

```

In Unix I would do the following: 

```
for ((i=1;i<4;i++))
do 
a = array$i[:,:,:]*1000
echo a 
done

```

This would give:

```
array1[:,:,:]
array2[:,:,:]
array3[:,:,:]

```

How can I do this in Python in a for loop?