What is the cleanest way to initialize dynamic list in Python?

Question

This is a question regarding best coding practices. Suppose I have to populate a list of unknown length; usually I just initialize the list with myList = [] , but I feel like this is a poor way of doing this. I often end up with chunks of code that look like this:

list1 = []
list2 = []
list3 = []

for a,b,c in zip(x,y,z):
    list1.append(a)
    list2.append(b)
    list3.append(c)

I realize in the example you can initialize this lists to the correct length, in fact you can just use x,y,z as they are. My question is regarding a situation in which you don't necessarily know the length of the lists. In my opinion, having to use three lines to initialize this lists is clunky; what do you guys thing? Thanks for any input!

Answer 1

No need for anything clever:

list1 = list(x)
list2 = list(y)
list3 = list(z)

Answer 2

Use a list of lists:

lol = [[], [], []]
for items in zip(x, y, z):
    for i, item in enumerate(items):
        lol[i].append(item)