Deleting from a list of mappings
Removing items from a list has an interesting consequence. Specifically, when item list[x] is removed, one of two other things will happen:
- Item
list[x+1]takes the place oflist[x] - Item
x+1 == len(list)takes the place oflist[x]becausexwas the last index in the list
These are side-effects that happen in addition to removing an item. Because things can move around in a list, it makes deleting more than one item at a time challenging.
When the list contains items that have a definition for the __eq__() special method, then the list remove() method can remove each item. When the list items don't have a simple __eq__() test, then it becomes more challenging to remove multiple items from the list.
How can we delete multiple items from a list?
Getting ready
We'll work with a list-of-dict structure. In this case, we've got some data that includes a song name, the writers, and a duration. The data looks like this:
>>> source = [
... {'title': 'Eruption...
