In the UI it would be nice to duplicate the selected connection, in the menu "With Selected". 

The copy would be set with the same name plus some suffix (_copy, _1, whatever) and it is useful for when you have a connection with all equal fields except something in a particular one. 
tests/www/views/test_views_connection.py
with create_session() as session:
        session.query(Connection).delete()
def test_create_connection(admin_client):
    init_views.init_connection_form()
    resp = admin_client.post('/connection/add', data=CONNECTION, follow_redirects=True)
    check_content_in_response('Added Row', resp)
def test_prefill_form_null_extra():
    mock_form = mock.Mock()
    mock_form.data = {"conn_id": "test", "extra": None}
    cmv = ConnectionModelView()
    cmv.prefill_form(form=mock_form, pk=1)