AsyncEtherScanApis support python 3.7.3 + aiohttp 3.0 + use: from etherscan import EtherScan async def main(): f = EtherScan(api_key="{token}") await f.open_session() # or Etherscan(api_key="{token}",session) print(await f.your_method()) asyncio.run(main())