Retrieve a file or directory listing in ASCII transfer mode. *cmd*
should be an appropriate ``RETR`` command (see :meth:`retrbinary`) or a
command such as ``LIST``, ``NLST`` or ``MLSD`` (usually just the string
- ``'LIST'``). The *callback* function is called for each line, with the
- trailing CRLF stripped. The default *callback* prints the line to
- ``sys.stdout``.
+ ``'LIST'``). The *callback* function is called for each line with a
+ string argument containing the line with the trailing CRLF stripped.
+ The default *callback* prints the line to ``sys.stdout``.
.. method:: FTP.set_pasv(boolean)