dict_concepts

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

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