diff --git a/sac/algos/sac_v2.py b/sac/algos/sac_v2.py
index 3adbf89..ebdd289 100644
--- a/sac/algos/sac_v2.py
+++ b/sac/algos/sac_v2.py
@@ -1,3 +1,5 @@
+from numbers import Number
+
 import numpy as np
 import tensorflow as tf