16_dict_difference.py

"""
Write a function, dictdiff, that takes two dicts as arguments. The function 
returns a new dict that expresses the difference between the two dicts.

If there are no differences between the dicts, dictdiff returns an empty dict. 
For each key-value pair that differs, the return value of dictdiff will have a 
key-value pair in which the value is a list containing the values from the two 
different dicts. If one of the dicts doesn’t contain that key, it should 
contain None.
"""

d1 = {'a':1, 'b':2, 'd':3}
d2 = {'a':1, 'b':2, 'c':4}

def dict_diff(d1, d2):
    output_dict = {}
    for key in d1.keys() | d2.keys():
        if d1.get(key) != d2.get(key):
            output_dict[key] = (d1.get(key), d2.get(key))
    return output_dict
            
print(dict_diff(d1, d2))