dict_concepts

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How do you examine every key and every value of a dictionary?
Call the examine() method on the dictionary. Use a for-each loop over the keys or items in the dictionary. Use a for loop over a range, examining each index i. Use [] on each key one at a time. Use the values to look up the keys. (order shuffled)
How do you check whether a given key is found in a dictionary in your code?
Call the exists() function on the dictionary. Use the keyword 'in' to test for membership. Print the dictionary and read the output. Use the [] operator on the dictionary. Add the key, and see if an error is raised. (order shuffled)
What happens if you try to add a key/value pair to a dictionary and it already has a pair with that same key?
An error is raised. The new pair is added and the old pair remains as well; both will be present in the dictionary. The new value replaces the old one for that key. Nothing happens; the new key/value are not added. An error message prints out on the console saying, "bad key or value." (order shuffled)
What happens if you try to add a key/value pair to a dictionary and it already has a pair with the same value, but not with the same key?
The new pair is added and the old pair remains as well; both will be present in the dictionary. Nothing happens; the new key/value are not added. An error message prints out on the console saying, "bad key or value." An error is raised. The new key/value pair replaces the old pair for that value. (order shuffled)
The key/value pairs in a dictionary are stored in an unpredictable order. How can you loop over the pairs in sorted order by the ordering of the keys?
Use a different collection, not a dictionary. You cannot; it is impossible. Be careful to add the keys in sorted order so that the dictionary will store them in sorted order. Copy the dictionary to a file, then sort the file. Call the sorted() function on the dictionary's keys. (order shuffled)

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