[Python] Why does creating a list inside or outside the for loop produce different results?

I'm creating a program that removes duplicate numbers from a list. The point of the exercise is to use "not in" and "in" operators.

The first time I created the code I created the list without the duplicates inside my for loop. I got a strange answer but I knew the code was correct. Moving the list creation outside the for loop produced the correct result and I dont understand why

Correct output:

my_list = [1, 2, 4, 4, 1, 4, 2, 6, 2, 9]

new_list = []
for i in my_list:
if i not in new_list:
new_list.append(i)

print("The list with unique elements only:")
print(new_list)


Incorrect output:

my_list = [1, 2, 4, 4, 1, 4, 2, 6, 2, 9]

for i in my_list:
new_list = []
if i not in new_list:
new_list.append(i)

print("The list with unique elements only:")
print(new_list)


My second code didn't work, it just produced the number 9 but my first piece of code (after moving the list creation statement outside the for loop) gave me the correct result.

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