Why so many browsers opened after I modified the pytest

I have 3 files:

• utlis.py is the base po for page actions
• login_page_po.py is the login page po
• test_login.py is the test I defined

utlis.py

class DriverUtil:
    """Common utils for browser"""

    def __init__(self, browser_type=0):
        if browser_type == 0:
            self.driver = webdriver.Chrome()
        elif browser_type == 1:
            self.driver = webdriver.Firefox()
        else:
            raise NameError('Invalid browser!')

    def openurl(self, url):
        self.driver.get(url)

    def find_element(self, value):
        return self.driver.find_element(By.CSS_SELECTOR, value)

    def get_text(self, value):
        return self.find_element(value).text

    def input_text(self, value, txt):
        self.find_element(value).send_keys(txt)

    def click_element(self, value):
        self.find_element(value).click()

    def quit_driver(self):
        self.driver.quit()

login_page_po.py

elementsMap = {
    'usernameInputField': 'input[name="username"]',
    'passwordInputField': 'input[name="password"]',
    'login_button': 'input[value="login"]',
    'error_message': 'div >p'
}

test_login.py

from utlis import DriverUtil
from login_page_po import elementsMap


class TestLogin:

    def setup_class(self):
        self.driver = DriverUtil()
        self.driver.openurl('https://www.stealmylogin.com/demo.html')

    def teardown_class(self):
        self.driver.quit_driver()

    def setup(self):
        self.driver.openurl('https://www.stealmylogin.com/demo.html')

    def test_wrong_username(self):
        self.driver.input_text(elementsMap['usernameInputField'], 'wrongadmin')
        self.driver.input_text(elementsMap['passwordInputField'], 'admin')
        self.driver.click_element(elementsMap['login_button'])

    def test_wrong_password(self):
        self.driver.input_text(elementsMap['usernameInputField'], 'admin')
        self.driver.input_text(elementsMap['passwordInputField'], 'wrongpassword')
        self.driver.click_element(elementsMap['login_button'])

So far I make both tests pass. One browser opens and 2 tests are executed and passed. But there are duplicated codes inside my test_login.py (see below)

        self.driver.input_text(elementsMap['usernameInputField'], 'wrongadmin')
        self.driver.input_text(elementsMap['passwordInputField'], 'admin')
        self.driver.click_element(elementsMap['login_button'])

I modified the duplicated via moving it to login_page_po.py. Now login_page_po.py looks like below

from utlis import DriverUtil

elementsMap = {
    'usernameInputField': 'input[name="username"]',
    'passwordInputField': 'input[name="password"]',
    'login_button': 'input[value="login"]',
    'error_message': 'div >p'
}

class Login:

    def __init__(self):
        self.driver = DriverUtil()
        self.driver.openurl('https://www.stealmylogin.com/demo.html')

    def login_method(self, username, password):
        self.driver.input_text(elementsMap['usernameInputField'], username)
        self.driver.input_text(elementsMap['passwordInputField'], password)
        self.driver.click_element(elementsMap['login_button'])

and test_login.py looks like below:

from utlis import DriverUtil
from login_page_po import Login


class TestLogin:

    def setup_class(self):
        self.driver = DriverUtil()
        self.driver.openurl('https://www.stealmylogin.com/demo.html')
        self.login = Login()

    def teardown_class(self):
        self.driver.quit_driver()

    def setup(self):
        self.driver.openurl('https://www.stealmylogin.com/demo.html')

    def test_wrong_username(self):
        self.login.login_method('wrongadmin', 'admin')

    def test_wrong_password(self):
        self.login.login_method('admin', 'wrongpassword')

Now the tests start failing and I can see 2 browsers opened when I executed the test and the 1st one doesn't do anything. The first test was executed on the 2nd opened browser. Did I do something wrong?