Add date_start in pass value

models/enercoop_operation.py

@@ -73,7 +73,8 @@ class EnercoopOperation(models.Model):
             date_min = date_min.strftime("%d/%m/%Y")
             result_graph.update({
                 'date_end': date_end,
-                'date_min': date_min
+                'date_min': date_min,
+                'date_start': date_start,
             })
 
         return result_graph