Why do I see an error

Error while making request to
https://data.similarweb.com/api/v1/data?domain=httpbin.org: Expecting
value: line 1 column 1 (char 0)

with aiohttp while requests.get returns the correct json?

import aiohttp
import asyncio
import nest_asyncio

nest_asyncio.apply()

async def fetch(session, url):
    try:
        async with session.get(url, headers=headers) as response:
            return await response.json(content_type=None)
    except Exception as e:
        print(f"Error while making request to {url}: {str(e)}")

async def fetch_all(urls):
    async with aiohttp.ClientSession() as session:
        tasks = []
        for url in urls:
            tasks.append(fetch(session, url))
        responses = await asyncio.gather(*tasks, return_exceptions=True)
        return responses

headers = {
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36',
}

urls = ['https://data.similarweb.com/api/v1/data?domain=' + 'httpbin.org']

responses = asyncio.run(fetch_all(urls))

httpbin.org/headers returns exactly the same headers with the only difference in X-Amzn-Trace-Id value.