Our electricity is supplied by Sainsbury's Energy, and they do not interface well with our smart meters.
This means we frequently end up with absolutely mental estimated bills, which is not that fun. I am also very bad at remembering to submit energy readings, and so I sniffed around their site until I figured out how the API worked, and then wrote this script which will submit the readings for me.
You too can use this if you so desire, simply by running submit_readings.py with the relevant command line args:
--email Your Sainsbury's Energy account email
--password Your Sainsbury's Energy account password
--gas An integer value to submit as the gas meter reading
--elec An integer value to submit as the electricity meter reading