python - tuple, set, dictionary

# Using dictionaries
stocks = {
    "GOOG": (1235.20, 1242.54, 1231.06),
    "MSFT": (110.41, 110.45, 109.84),
}

random_keys = {}
random_keys["astring"] = "somestring"
random_keys[5] = "aninteger"
random_keys[25.2] = "floats work too"
random_keys[("abc", 123)] = "so do tuples"


class AnObject:
    def __init__(self, avalue):
        self.avalue = avalue


my_object = AnObject(14)
random_keys[my_object] = "We can even store objects"
my_object.avalue = 12
try:
    random_keys[[1, 2, 3]] = "we can't store lists though"
except:
    print("unable to store list\n")

for key, value in random_keys.items():
    print("{} has value {}".format(key, value))

>>
unable to store list

astring has value somestring
5 has value aninteger
25.2 has value floats work too
('abc', 123) has value so do tuples
<__main__.AnObject object at