How would you list the people from a database that are not from 'London'?
Say the database is:

```
Cust_id         address
  1             33 avenue, Liverpool
  2             21 street 12345, London 
  3             469 connection ave, Manchester

```

I'd like to list the customers that are NOT from London. Here's what I've tried:

```
select Cust_id from customers where address <> 'London';

```

Now when I do that, it lists all the customers, regardless of location.

Help would be greatly appericated.