[Python] Confused about declaring lists outside vs. inside loops and creating them empty vs....

I'm learning about creating a list of lists. For this particular section, this was the correct code:

numerical_list = []

for line in nested_list:
name = line[0]
count = float(line[1])
new_list = [name, count]
numerical_list.append(new_list)

print(numerical_list[0:5])


They give you a little bit of instruction, including creating the empty numerical_list before starting the loop, but I'm slightly confused as to why I need to declare that empty list while, in the body of the loop, I was able to create

new_list = [name, count]


Without declaring it outside. I think I get it, but I want to be sure.

My understanding is that, because numerical_list is empty, it needs to be declared outside of the loop so that it exists and then, on the line

numerical_list.append(new_list)


I'm inserting an element into it. Meanwhile, because I'm declaring new_list with arguments, it already has elements and they don't need to be inserted separately. Is that correct?

In other words, is this correct: new, empty lists cannot be created inside a loop but new lists with arguments can.

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