How to search through dictionaries?

Simple enough

if entry in people:
    print ("Name: " + entry)
    print ("Age: " + str(people[entry]) + "\n")

Python also support enumerate to loop over the dict.

for index, key in enumerate(people):
    print index, key, people[key]

If you want to know if key is a key in people, you can simply use the expression key in people, as in:

if key in people:

And to test if it is not a key in people:

if key not in people:

You can reference the values directly. For example:

>>> people = {
... "Austun": 25,
... "Martin": 30}
>>> people["Austun"]

Or you can use people.get(<Some Person>, <value if not found>).

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