Level 1 : Factorial sequence. 


import math

class FactorialIterator:
    def __init__(self, n):
        self.n = n
        self.current = 0

    def __iter__(self):
        return self

    def __next__(self):
        if self.current > self.n:
            raise StopIteration
        value = math.factorial(self.current)
        self.current += 1
        return value

it = iter(FactorialIterator(4))
print(list(it))
Author: SandhyaR | Tags: iterator | 1859+ Python FAQs | Share
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