added function for serialization of None, True, False or Inconclusive

smash/web/api_views/serialization_utils.py

@@ -18,6 +18,16 @@ def bool_to_yes_no_null(val):
     else:
         return "NO"
 
+def virus_test_to_str(test, date):
+    if test is None and date is not None:
+        return "Inconclusive"
+    if test is None:
+        return "N/A"
+    if test:
+        return "YES"
+    else:
+        return "NO"
+
 
 def flying_team_to_str(flying_team):
     result = ""