I have a python dictionary which looks like this:

```py
test_dict = {'id': '00000001',
             '2017': {'some_info': 'toast'},
             '2018': {'some_more_info': 'bread'},
                       }

```

I want to access the most recent year but the most recent year could change every time. 

I have tried converting each key to an integer if it is possible ('id' obviously won't convert to an integer) using:

```py
new_d = {}
for k,v in test_dict.items():
    try:
        new_d[int(k)] = v

    except ValueError:
        new_d[k] = v

```

Then tried to find the max key:

```py
max(new_d, key=int)

```

But I still have the error:
`ValueError: invalid literal for int() with base 10: '_id'` which makes sense. 

I want to search the dictionary for the max value key for all keys which are integers. 

In this example I want to access the 2018 nested dictionary.