Python function with default argument inside loop

Question

for i in range(5):
   def test(i=i):
      print(i)

test()
test()
test()
test()
test()

This prints 4 every time? Can someone help me understanding this.

Answer 1

The function test is redefined every iteration of the loop.

By the time the loop is done, test is simply:

def test(i=4):
    print(i)

Answer 2

You redefine the test 4 times:

same as:

#define test
def test(i = 0):
    print(i)

#redefine test
def test(i = 1):
    print(i)

#redefine test
def test(i = 2):
    print(i)

#redefine test
def test(i = 3):
    print(i)

#redefine test
def test(i = 4):
    print(i)

so you have only 1 test() the last one.