Replace deprecated save_virtual_workbook

https://foss.heptapod.net/openpyxl/openpyxl/-/blob/3.0.10/openpyxl/writer/excel.py#L297
https://openpyxl.readthedocs.io/en/3.1/tutorial.html#saving-as-a-stream

Author: kemar

plugins/polio/api/campaigns/campaigns.py

@@ -2,6 +2,7 @@
 import json
 from time import gmtime, strftime
 from typing import Any, List, Union
+from tempfile import NamedTemporaryFile
 
 from django.conf import settings
 from django.core.cache import cache
@@ -17,7 +18,7 @@
 from django.utils.translation import gettext as _
 from django_filters.rest_framework import DjangoFilterBackend  # type: ignore
 from gspread.exceptions import APIError  # type: ignore
-from openpyxl.writer.excel import save_virtual_workbook  # type: ignore
+from openpyxl import Workbook
 from rest_framework import filters, permissions, serializers, status
 from rest_framework.decorators import action
 from rest_framework.fields import Field
@@ -822,10 +823,12 @@ def create_calendar_xlsx_sheet(self, request, **kwargs):
         filename = xlsx_file_name("calendar", params)
         xlsx_file = generate_xlsx_campaigns_calendar(filename, calendar_data)
 
-        response = HttpResponse(
-            save_virtual_workbook(xlsx_file),
-            content_type=CONTENT_TYPE_XLSX,
-        )
+        with NamedTemporaryFile() as tmp:
+            xlsx_file.save(tmp.name)
+            tmp.seek(0)
+            stream = tmp.read()
+
+        response = HttpResponse(stream, content_type=CONTENT_TYPE_XLSX)
         response["Content-Disposition"] = "attachment; filename=%s" % filename + ".xlsx"
         return response