Answer #2

import time
import aiohttp
import asyncio


async def get_page(session, category: str, page_id: int) -> str:
    if page_id:
        url = f'https://www.ozon.ru/brand/{category}/?page={page_id}'
    else:
        url = f'https://www.ozon.ru/brand/{category}/'
    print(f'get url: {url}')
    async with session.get(url) as response:
        return await response.text()


async def load_data():
    category_list = ['adidas-144082850', 'puma-87235756']

    tasks = []
    async with aiohttp.ClientSession() as session:
        for category in category_list:
            for page_id in range(50):
                tasks.append(get_page(session, category, page_id))

        results = await asyncio.gather(*tasks)
        for text in results:
            pass
            # обрабатываем полученный текст, сохраняем в файл/базу


if __name__ == '__main__':
    start_time = time.time()
    loop = asyncio.get_event_loop()
    loop.run_until_complete(load_data())
    print("--- %s seconds ---" % (time.time() - start_time))