diff --git a/tqdm/_tqdm.py b/tqdm/_tqdm.py
index 71e05b2a..e80091be 100755
--- a/tqdm/_tqdm.py
+++ b/tqdm/_tqdm.py
@@ -478,7 +478,9 @@ class tqdm(Comparable):
         """
         with cls._lock:
             try:
-                cls._instances.remove(instance)
+                if instance in cls._instances:
+                    # in python2 instance maybe magically removed from cls._instances
+                    cls._instances.remove(instance)
             except KeyError:
                 if not instance.gui:  # pragma: no cover
                     raise