How can I generate a sas token with "sp" prefix and not "sv" when using get_services_sas?

Hii, I am currently trying to generate a sas token via the following code:

```
get_service_sas(account = "",
key = "",
service = "file",
resource="",
resource_type="b",
permissions="r")
```

I specifically need it to generate with "sp" in front and not "sv" as the token I was creating on Azure had that and none of the "sv" tokens so far have worked. How can I change this or what am I missing?