Description
When using Django with the recommended psycopg[c] v3 adapter and Elastic APM enabled, executing a QuerySet.iterator() fails with: TypeError: keyword not supported: prepare.

This occurs because psycopg v3’s server-side cursor implementation rejects the prepare=keyword argument, which is being passed through Elastic APM's database instrumentation.

To Reproduce

1. Install Django with the recommended PostgreSQL adapter (psycopg[c] v3.2.12).
2. Enable Elastic APM in the Django project.
3. Execute a Django query using QuerySet.iterator(), for example:

for obj in MyModel.objects.iterator():
    ...

Environment

• OS: Linux, Debian
• Python version: 3.12.12
• Framework and version Django 4.2
• APM Server version: 9
• Agent version: 6.24.0
• Server side cursors: enabled

Expected behavior:
The queryset should be processed normally using a server-side cursor without errors.

Actual behavior:
TypeError is raised: keyword not supported: prepare

psycopg/_server_cursor.py in execute at line 88

   ) -> Self:
        """
        Open a cursor to execute a query to the database.
        """
        if kwargs: # <---- here {"prepare": None}
            raise TypeError(f"keyword not supported: {list(kwargs)[0]}")

        if self._pgconn.pipeline_status:
            raise e.NotSupportedError(
                "server-side cursors not supported in pipeline mode"
            )

Additional context

• The error does not occur if Elastic APM is disabled.
• The error does not occur when using the not-recommended psycopg v2
• The issue appears to be caused by Elastic APM adding a prepare=None parameter during its instrumentation of database queries.