Move the zeros to the end

Rearrange a list so every zero is at the end and the other values keep their order, without making a new list. Use a writer position: walk the list with a reader, and every time the reader finds a non-zero value, put it at the writer's position and advance the writer. When the reader is done, fill from the writer to the end with zeros.

Write move_zeros(nums) that modifies the list in place and returns it.

move_zeros([0, 1, 0, 3, 12])  ->  [1, 3, 12, 0, 0]

def move_zeros(nums):
    ...