Iterator [Python] iter(), next()

# Python 3 : Iterator

a = [1, 2, 3]

a_iter = iter(a)

print(type(a_iter)) # <class 'list_iterator'>

print(next(a_iter)) # 1

print(next(a_iter)) # 2

print(next(a_iter)) # 3

print(next(a_iter)) # StopIteration