Summing nested dictionaries

Write a function sum_nested that takes a dictionary d and sums up every int and float inside it, including those in nested dictionaries. You should ignore nested lists or other types. Your code should not use exceptions in any way, i.e., it shouldn’t raise any exceptions and shouldn’t use try/ except.

Here are some examples:

>>> d1
{'a': 1, 'b': '2', 'c': 3}
>>> sum_nested(d1)
4
>>> d2
{'a': 1, 'b': '2', 'c': {'x': 1, 'y': [4, 5], 'z': 2}}
>>> sum_nested(d2)
4
>>> sum_nested({})
0