The hologram API / SDK will not work with 3rd party hardware, especially those not based on the same cellular modems (U-blox various PNs). If you want to use the SIM800L or anything not from Hologram, you will have to write your own SDK that use AT commands. This is because each module behaves differently and has a different set of AT commands for things like establishing HTTP / TCP connections, sending data, setting up the APN, etc. This is true even within the same manufacturer, for example the code for the SIM800 will not work with the SIM7000 series.
If you want to use Hologram’s python SDK / CLI you will basically have to use the Nova. Hologram has a (not officially supported) sample library for Arduino’s interfacing with the SIM800 series you can try to re-implement in python if you want to stick with the SIM800 series hardware and take on some additional software workload.