import os
import time
import random
import string

@pytest.fixture(scope="class")
def delay():
    asyncio.sleep(300)


@pytest.mark.usefixtures("delay")
class CoreTest:
    RUCAPTCHA_KEY = os.getenv("RUCAPTCHA_KEY", "ad9053f3182ca81755768608fa758570")

    def get_random_string(self, length: int) -> str:
        """
        Method generate random string with set length
        : param length: Len of generated string
        : return: Random letter string
        """
        # choose from all lowercase letter
        letters = string.ascii_lowercase
        result_str = "".join(random.choice(letters) for _ in range(length))
        return result_str

import os
import time
import random
import string
import pytest

@pytest.fixture(scope="class")
def delay():
    asyncio.sleep(300)


@pytest.mark.usefixtures("delay")
class CoreTest:
    RUCAPTCHA_KEY = os.getenv("RUCAPTCHA_KEY", "ad9053f3182ca81755768608fa758570")

    def get_random_string(self, length: int) -> str:
        """
        Method generate random string with set length
        : param length: Len of generated string
        : return: Random letter string
        """
        # choose from all lowercase letter
        letters = string.ascii_lowercase
        result_str = "".join(random.choice(letters) for _ in range(length))
        return result_str

Update conftest.py