diff --git a/docs/requirements.txt b/docs/requirements.txt
index e3cc898..6b3c14f 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,2 +1,3 @@
 numpydoc>=0.5
-numpy>=1.9.0
\ No newline at end of file
+numpy>=1.9.0
+typing-extensions