task_5.py

import os
import csv

class Iterator1:
    def __init__(self, rating: str) -> None:
        self.file_names = os.listdir(os.path.join('dataset', rating))
        self.limit = len(self.file_names)
        self.counter = 0
        self.rating = rating
        
    def __next__(self) -> str:
        if self.counter < self.limit:
            self.counter += 1
            return os.path.join(self.rating, self.file_names[self.counter-1])
        else:
            raise StopIteration
        
class Iterator2:
    def __init__(self, rating: str) -> None:
        if (5<int(rating) or int(rating)<1):
            raise KeyError
        self.file_names = []
        for name in os.listdir('dataset_copy'):
            if rating == name[0]:
                self.file_names.append(name)
                
        self.limit = len(self.file_names)
        self.counter = 0
        self.rating = rating
        
    def __next__(self) -> str:
        if self.counter < self.limit:
            self.counter += 1
            return os.path.join(self.file_names[self.counter-1])
        else:
            raise StopIteration

a = Iterator1('1')
for i in range(10):
    print(next(a))