I have a dataframe

```
city = pd.DataFrame({'id': [1,2,3,4],
                        'city': ['NRTH CAROLINA','NEW WST AMSTERDAM','EAST TOKYO','LONDON STH']})

```

How can I change NRTH to NORTH, WST to WEST, and STH to SOUTH, so the output will be like this

```
id   city
1    NORTH CAROLINA
2    NEW WEST AMSTERDAM
3    EAST TOKYO
4    LONDON STH

```