[cairo] pip3 pycairo installation help on MacOS

[Bob Lewis]

I've used pip (pip3, actually) under MacOS before, but not come across this
problem. This transcript tells all:

$ pip3 search pycairo
pycairo (1.10.0)             - Python bindings for the cairo library
tl.buildout_gtk (0.2.2)      - A zc.buildout recipe for installing pygtk,
                                pyobject and pycairo.
yaco.recipe.pycairo (0.1.1)  - Buildout recipe for compiling pycairo
$ pip3 install pycairo
Collecting pycairo
   Could not find a version that satisfies the requirement pycairo (from versions: )
No matching distribution found for pycairo

It looks like the package is there, but cannot be installed. Is this
a pip problem or a pycairo problem?

     - Bob Lewis