feat: 更新证书查询创建图片后端3

server/apps/edu/views.py

@@ -27,7 +27,7 @@ class CertificateViewSet(CreateUpdateCustomMixin, ModelViewSet):
     def retrieve(self, request, *args, **kwargs):
         regen_img = request.query_params.get('regen_img', False)
         instance = self.get_object()
-        if instance.证书地址 is None or regen_img:
+        if not instance.证书地址 or regen_img:
             titles = []
             if instance.是否内审员:
                 titles.append('内审员')