+Progress bar
+============
+
+To allow ``ml-import.py`` to display progress bar the program requires
+library ``m_lib``. You can install the library separately using, e.g.,
+command ``pip install m_lib``. Or you can install the library with
+``m_librarian``: ``pip install m_librarian[pbar]``.
+
+Other extras
+============
+
+``pip install m_librarian[web]`` installs libraries needed for web-ui.
+
+``pip install m_librarian[wx]`` installs a library needed for wx GUI
+(``wxPython``).