FAQ: Creating Dictionaries - Invalid Keys

[wiki-bot]

This community-built FAQ covers the “Invalid Keys” exercise from the lesson “Creating Dictionaries”.

Paths and Courses
This exercise can be found in the following Codecademy content:

Computer Science

FAQs on the exercise Invalid Keys

• Can a tuple be used as a dictionary key?
• What does it mean that certain datatypes cannot be keys?

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[mega8692770800]

Can you plot your dictionary key values in matplotlib?
dict = {x: [1,2,3,4,], y:[2,4,6,6]}

[stetim94]

Have you tried to use a search engine to see if there might be an existing answer to this question?

[data4497678054]

Is there a way to swap key:value pairs quicker than to do so manually, similar to how we were asked in the “Invalid Keys” exercise?

I have tried the following, however, the traceback that arises due to the invalid dictionary convention in the first line prevents the programme from running to the block of code that performs the swap:

children = {["Johannes", "Rosmarie", "Eleonore"]: "von Trapp", ["Sonny", "Fredo", "Michael"]: "Corleone"}

swapped_children = {value: key for key, value in children.items()}
print(swapped_children)

Thanks.

[mtrtmk]

children is not a valid dictionary because:

Source: https://docs.python.org/3/tutorial/datastructures.html#dictionaries

If the keys in children were tuples of strings, then your code would work.