This is used to generate ppd files for cups:
$ cups-genppd.5.2 -M | grep p50
canon-cp500
escp2-p50
$ cups-genppd.5.2 -p . escp2-p50
This will create the relevant ppd file in the current directory. This
can then be used by cups after setting services.drivers.drivers =
[pkgs.gutenprint]; and configuring the printer to use this ppd e.g.
via the web interface on http://localhost:631