[{'Text': '    mock_response = json.dumps({"ok": False, "error": f"Duplicate exists (id={existing_id})"})\n\n    with patch("point_topic_mcp.core.mongodb_utils.insert_statistic_safe", return_value=mock_response):\n        result = gbs.add_statistic(type="broadband", operator_id=str(ObjectId()), period="2025Q3", tech="FTTP", channel="Infrastructure", domain="Residential", subscribers=50000)\n        assert "Duplicate" in result\n        assert existing_id in result\n\n\n# --- create_source tests ---\n\ndef test_create_source_validation(gbs_env):\n'}]