[Paraview] How do I install a python macro?

[Ken Olum]

I am a new ParaView user.  I'm using 3.8.0.  I understand there's a
facility for writing macros in python and putting them in a toolbar.
I can type the code I want the macro to execute into the python shell,
but I don't understand how to get it established as a macro.  I can't
seem to find any documentation.  In
http://www.itk.org/Wiki/Python_GUI_Tools#Macros it says

   Macros allow the user to define a Python script as built-in actions
   that become accessible from the Macros menu or directly inside the
   Toolbar.

   Once a local file is defined as a Macro...

This is what I want, and indeed I see the "Macros" menu and the
toolbar, both empty.  So how do I perform this operation of defining a
local file as a macro?

Thanks.

                                        Ken Olum