According to the docs in paramiko the return type will always be bytes
```
.. note::
``'b'`` mode flag is ignored (``self.FLAG_BINARY`` in
``self._flags``), because SSH treats all files as binary, since we
have no idea what encoding the file is in, or even if the file is
text data.
:param int size: maximum number of bytes to read
:returns:
data read from the file (as bytes), or an empty string if EOF was
encountered immediately
```
This doesn't cover everything but it means it a lot of common usages the type will be slightly more useful
Co-authored-by: steve brazier <steve.brazier@trioptima.com>
Steve B