According to the explanation of [typing.ByteString](https://docs.python.org/3/library/typing.html#typing.ByteString), it seems like a bytestring is the same as a [bytes-like-object](https://docs.python.org/3/glossary.html#term-bytes-like-object) in Python. So, [the glossary](https://docs.python.org/3/glossary.html) should also explain a bytestring and say a bytestring and bytes-like-object are the same in Python.