Is it possible to statically define a dictionary which contains another dictionary without using another variable?

Frequently Asked Questions Python FAQ
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Question

In this exercise, one of the values in the library dictionary is set from the plays dictionary. Is it possible to statically define a dictionary which contains another dictionary as a value?

Answer

Yes, when you define the dictionary you simply define another dictionary inside the {} brackets. The following code example shows a population dictionary which contains dictionaries for each state that contains cities and population numbers.

population = {"California": {"Los Angeles": 3971883,
                             "San Diego": 1394928,
                             "San Jose": 1026908},
              "Texas": {"Houston": 2296224,
                        "San Antonio": 1469845}
              }
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looping through this to pull out information i am sure is possible but seems daunting. Better to keep it simple and create several dictionaries?

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Nested data structures are common. You should rise to the occasion (challenge? No idea, my english isn’t that good)

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My melting brain is screaming “thiiiis wiiiilll beeee fuuuuun”

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:rofl: I’m glad I’m not the only one who’s brain is getting fried.

Here’s a simple way to extract nested values:

print(library["The Best Songs"]["Imagine"])
// Prints out 44

Much like retrieving data from nested lists/arrays, of course.

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For this question asked by @ajaxninja66418 , If I want to update the values “California”, how would I go about it?Eg. I want to add more cities in California with their relative population count… how would the code be written?

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I would say the same way you add something to a dictionary:

my_dict['new_key"] = "new value"

but you will first need to look-up California in the population dictionary.

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population['California'].update({'San Francisco': 873965, 'Fresno': 542107})

We can do it by this piece of code.`

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