The override guarded on self.code, which is empty on the model-level
recordset passed to create(), so the branch never ran. The private key is
generated during pairing (in the onchange) instead, so the override is
dead code; removing it also keeps copying a provider from regenerating
(and thus invalidating) an already paired key.
The bundled BTCPay client (models/libs) imports ecdsa, while the manifest
and requirements only listed btcpay-python, which is not used (the client
is vendored). Installations that did not already have ecdsa available
failed the external-dependency check. Declare ecdsa instead and bump the
module version.
SatoDri