Accessing Sentinel 1 soil moisture (1 km) through API

Hi there,

I have previously used the Open Search Catalogue and this tutorial to access SLSTR data. I now wish to do the same for Sentinel 1 soil moisture (1 km). The Copernicus Land Monitoring Service states that I can access it through the API, but I’m not sure what https address to give the process, to find the 1km Soil Moisture product.

So far, I have tried

json = requests.get(",40,5,43&productType=L2_SM_SP").json()

but I think I am getting a bit confused. If anyone has managed to access Sentinel 1 Soil Moisture (1km), I would really appreciate any advice