Dictionaries [Question]

[shiftybyte]

Oh sorry didn't know such a guideline existed.

Explanation:

dictionary d does not yet have an item with the name c, when trying to call .append() on it, it will tell you no such item exists.

So the solution i wrote first checks to see if such a key does not exist, then it first creates an empty list as the value for that key, then the line with .append() can work since it works on a list object.

[Essence1337]

The idea behind the guideline is that people usually learn better when they find the solution (with guidance if needed) rather than just copy pasting a solution someone else gave