diff --git a/api/s0_base.py b/api/s0_base.py
index 6588846..a361435 100644
--- a/api/s0_base.py
+++ b/api/s0_base.py
@@ -43,7 +43,7 @@ def is_tank(name: str, id: str) -> bool:
 
 
 def is_link(name: str, id: str) -> bool:
-    return _get_from(name, id, _LINK) != {}
+    return _get_from(name, id, _LINK) != None
 
 
 def is_pipe(name: str, id: str) -> bool: