output for result_var name is not needed

python_code_executor_service.py

@@ -45,8 +45,8 @@ class CsvChatResult(BaseModel):
     casual_response: str
     # analysis_operations: List[AnalysisOperation]
     # charts: Optional[List[ChartSpecification]] = None
-    analysis_operations: AnalysisOperation
-    charts: ChartSpecification = None
+    analysis_operations: Optional[AnalysisOperation] = None
+    charts: Optional[ChartSpecification] = None
 
 
 class PythonExecutor:
@@ -200,7 +200,7 @@ class PythonExecutor:
         output_parts = [response.casual_response]
     
         # Process single analysis operation
-        if response.analysis_operations:
+        if response.analysis_operations is not None:
             operation = response.analysis_operations
             execution_result = self.execute_code(operation.code.code)
         
@@ -223,7 +223,7 @@ class PythonExecutor:
                 output_parts.append("```\n" + output_str + "\n```")
                 
         # Process single chart
-        if response.charts:
+        if response.charts is not None:
             output_parts.append("\n📊 Visualizations:")
         chart = response.charts
         if chart.code: