I am a beginner in Google App Engine. I am trying to get the data of Klaviyo from Flask to Google Cloud Storage. When I run the code at my computer, everything runs very well, but after I push all my code in the Google Server, the data always gets null. In the code, I have had to calculate the values and I get integer and float data types. I tried to change schema, but the code does not work in the server. Then I convert it into string types, and the same problem occurs.

Please help me.

This is my code:

@app.route("/append_klaviyo_data")
def append_klaviyo_data():
    """Return a friendly HTTP greeting."""
    try:
        dt = data_handler()
        local_timezone = tzlocal.get_localzone()
        current_time = datetime.now(local_timezone)

        metrics = dt if isinstance(dt, list) and len(dt) == 12 else [""] * 12

        open_rate = metrics[0]
        click_rate = metrics[1]
        unsubscribed_rate = metrics[2]
        bounce_rate = metrics[3]
        delivery_rate = metrics[4]
        conversion_active_on_site_rate = metrics[5]
        conversion_viewed_product_rate = metrics[6]
        revenue_per_email = metrics[7]
        product_purchase_rate = metrics[8]
        average_order_value = metrics[9]
        subscriber_count = metrics[10]
        new_subscriber_count = metrics[11]

        date = current_time.strftime("%m-%d-%Y")
        results = {
            "date": [date, date],
            "title": ["Active on Site", "Viewed Product"],
            "open_rate": [open_rate, open_rate],
            "click_rate": [click_rate, click_rate],
            "unsubscribed_rate": [unsubscribed_rate, unsubscribed_rate],
            "bounce_rate": [bounce_rate, bounce_rate],
            "delivery_rate": [delivery_rate, delivery_rate],
            "conversion_rate": [
                conversion_active_on_site_rate,
                conversion_viewed_product_rate,
            ],
            "revenue_per_email": [revenue_per_email, revenue_per_email],
            "product_purchase_rate": [product_purchase_rate, product_purchase_rate],
            "average_order_value": [average_order_value, average_order_value],
            "new_subscribers": [
                new_subscriber_count,
                new_subscriber_count,
            ],
            "subscriber_counts": [
                subscriber_count,
                subscriber_count,
            ],
        }

        klaviyo_df = pd.DataFrame(results)

        client = bigquery.Client()

        print("size of dataframe = " + str(klaviyo_df.shape[0]))

        job_config = bigquery.LoadJobConfig(
            write_disposition="WRITE_APPEND"
        )

        job = client.load_table_from_dataframe(
            klaviyo_df, f"{project_id}.{dataset_id}.{table_name}", job_config=job_config
        )
        job.result()

        table = client.get_table(f"{project_id}.{dataset_id}.{table_name}")

        print(
            "Loaded {} rows and {} columns to {}".format(
                table.num_rows,
                len(table.schema),
                f"{project_id}.{dataset_id}.{table_name}",
            )
        )

        print(
            "Total records logged to BigQuery for Klaviyo =  "
            + str(klaviyo_df.shape[0])
        )
        return "Klaviyo Results Logged!"
    except Exception:
        ex_type, ex_value, ex_traceback = sys.exc_info()
        trace_back = traceback.extract_tb(ex_traceback)
        stack_trace = list()
        for trace in trace_back:
            stack_trace.append(
                "File : %s , Line : %d, Func.Name : %s, Message : %s, Exception type: %s, Exception message: %s"
                % (trace[0], trace[1], trace[2], trace[3], ex_type, ex_value)
            )
        return stack_trace
    finally:
        return metrics

def get_data() -> list:
    try:
        # Initialize variables
        metrics = {
            "delivered_email_count": 0,
            "bounced_email_count": 0,
            "spam_email_count": 0,
            "dropped_email_count": 0,
            "opened_email_count": 0,
            "clicked_email_count": 0,
            "unsubscribed_count": 0,
            "conversion_active_on_site_count": 0,
            "conversion_viewed_product_count": 0,
            "revenue_unique_count": 0,
            "total_revenue_count": 0,
            "total_order_count": 0,
            "delivered_email_unique_count": 0,
            "revenue_count": 0,
            "subscriber_count": 0,
            "new_subscriber_count": 0,
        }
        return [metrics[key] for key in metrics]



def data_handler():
    dt = get_data()
    if isinstance(dt, list) and len(dt) == 16:
        (
            delivered_email_count,
            bounced_email_count,
            spam_email_count,
            dropped_email_count,
            opened_email_count,
            clicked_email_count,
            unsubscribed_count,
            conversion_active_on_site_count,
            conversion_viewed_product_count,
            revenue_unique_count,
            total_revenue_count,
            total_order_count,
            delivered_email_unique_count,
            revenue_count,
            subscriber_count,
            new_subscriber_count,
        ) = dt
    else:
        # Handle the case where get_data() returns an error or unexpected result
        return dt

    total_recipients = (
        delivered_email_count
        + bounced_email_count
        + spam_email_count
        + dropped_email_count
    )
    open_rate = calculate_rate_metric(opened_email_count, delivered_email_count)
    click_rate = calculate_rate_metric(clicked_email_count, delivered_email_count)
    unsubscribed_rate = calculate_rate_metric(unsubscribed_count, total_recipients)
    bounce_rate = calculate_rate_metric(bounced_email_count, total_recipients)
    delivery_rate = calculate_rate_metric(delivered_email_count, total_recipients)
    conversion_active_on_site_rate = calculate_rate_metric(
        conversion_active_on_site_count, delivered_email_count
    )
    conversion_viewed_product_rate = calculate_rate_metric(
        conversion_viewed_product_count, delivered_email_count
    )
    revenue_per_email = (
        revenue_count / delivered_email_count if delivered_email_count != 0 else 0
    )
    product_purchase_rate = calculate_rate_metric(
        revenue_unique_count, delivered_email_unique_count
    )
    average_order_value = (
        total_revenue_count / total_order_count if total_order_count != 0 else 0
    )

    return [
        str(open_rate),
        str(click_rate),
        str(unsubscribed_rate),
        str(bounce_rate),
        str(delivery_rate),
        str(conversion_active_on_site_rate),
        str(conversion_viewed_product_rate),
        str(revenue_per_email),
        str(product_purchase_rate),
        str(average_order_value),
        str(subscriber_count),
        str(new_subscriber_count),
    ]

I am trying to upload the data from Klaviyo to Google Cloud Storage