We want to store documents and let RavenDB assign Guid identifiers to the documents. From the documentation:

Then, you have to provide the string.Empty as the value of the Id property

We have tried setting the Id = "" but receive the error below when saving changes. However, the document is correctly stored in the database with id() = guid and Id = "".
Setting Id = None the document stores without an error but the id() and Id are set to the form: products/1-A.

Traceback:
File "raven_crud.py", line 77, in store_registration
session.save_changes()
File "ravendb/documents/session/document_session.py", line 134, in save_changes
save_changes_operation.set_result(command.result)
File "ravendb/documents/operations/batch.py", line 72, in set_result
self.__on_successful_request.clear_session_state_after_successful_save_changes()
File "ravendb/documents/session/document_session_operations/in_memory_document_session_operations.py", line 1825, in clear_session_state_after_successful_save_changes
self.__session._documents_by_id.pop(key)
File "ravendb/tools/utils.py", line 192, in pop
return super(CaseInsensitiveDict, self).pop(self.class._lower_if_str(key), *args, **kwargs)
KeyError: ''