A weighted version of random.choice

Question

I needed to write a weighted version of random.choice (each element in the list has a different probability for being selected). This is what I came up with:

Answer 1

If you have a weighted dictionary instead of a list you can write this

items = { "a": 10, "b": 5, "c": 1 } 
random.choice([k for k in items for dummy in range(items[k])])

Note that [k for k in items for dummy in range(items[k])] produces this list ['a', 'a', 'a', 'a', 'a', 'a', 'a', 'a', 'a', 'a', 'c', 'b', 'b', 'b', 'b', 'b']