iPython
In [1]: staff = {1: 'test1', 2: 'test2', 3: 'test3'}
In [2]: staff[4] = 'test4'
In [3]: staff
Out[3]: {1: 'test1', 2: 'test2', 3: 'test3', 4: 'test4'}
Python
iPython
In [1]: staff = {1: 'test1', 2: 'test2', 3: 'test3'}
In [2]: staff[4] = 'test4'
In [3]: staff
Out[3]: {1: 'test1', 2: 'test2', 3: 'test3', 4: 'test4'}