Page Object Pattern Circular import problem in Python-CodePudding

I'm writing my automation framework in Page Object Pattern and I've came across this error when implementing view classes. I've placed this classes in separate modules and I want them to stay separated. The problem is that I want my instance methods in both classes to return an object of another class when performing certain UI actions.

Is there a way to fix circular error while having this classes in separate modules?

cart_page.py

from pages.base_page import BasePage
from utils.locators import CartLocators
from pages.main_page import MainPage

class CartPage(BasePage):
    def __init__(self, driver):
        self.locators = CartLocators()
        super().__init__(driver, 'https://www.saucedemo.com/cart.html')

    def click_continue_shopping(self):
        self.find_element(*self.locators.CONTINUE_SHOPPING_BTN).click()
        return MainPage(self.driver)

main_page.py

from pages.base_page import BasePage
from utils.locators import MainPageHeaderLocators, MainPageItemListLocators, InventoryItemLocators
from pages.cart_page import CartPage

class MainPage(BasePage):
    def __init__(self, driver):
        super().__init__(driver, "https://www.saucedemo.com/invetory.html")
        self.header = MainPageHeader(self.driver)
        self.item_list = MainPageItemList(self.driver)
        self.inventory_item = InventoryItemPage(self.driver)

    def open_cart(self):
        self.header.open_cart()
        return CartPage(self.driver)

E   ImportError: cannot import name 'MainPage' from partially initialized module 'pages.main_page' (most likely due to a circular import) (/Users/marcin94/PycharmProjects/sauce_demo_ui_tests/pages/main_page.py)

CodePudding user response：

Do not use from. Import the module directly:

cart_page.py

from pages.base_page import BasePage
from utils.locators import CartLocators
import pages.main_page

class CartPage(BasePage):
    def __init__(self, driver):
        self.locators = CartLocators()
        super().__init__(driver, 'https://www.saucedemo.com/cart.html')

    def click_continue_shopping(self):
        self.find_element(*self.locators.CONTINUE_SHOPPING_BTN).click()
        return pages.main_page.MainPage(self.driver)

main_page.py

from pages.base_page import BasePage
from utils.locators import MainPageHeaderLocators, MainPageItemListLocators, InventoryItemLocators
import pages.cart_page

class MainPage(BasePage):
    def __init__(self, driver):
        super().__init__(driver, "https://www.saucedemo.com/invetory.html")
        self.header = MainPageHeader(self.driver)
        self.item_list = MainPageItemList(self.driver)
        self.inventory_item = InventoryItemPage(self.driver)

    def open_cart(self):
        self.header.open_cart()
        return pages.cart_page.CartPage(self.driver)