Ruby is one of the languages to have the most elegant and consistent standard library. It is just few standard patterns to learn to get productive.

I found Python's stdlib confusing. Is it list.sort() or sorted(list)? str.encode('UTF-8') to bytes and bytes.decode('UTF-8'). The string instance is already encoded in 'UTF-8'.

  async for item in fetch_data_stream():
      print(item)

Using async when infact you are `await`ing for items from fetch_data_stream() generator.