diff --git a/backends/cbackend.py b/backends/cbackend.py
index 84efdb9ffe413aa9c8623a45aeb7c011359eba14..45c31142cee9ff7a8d9d92ce3dd6c3ebb5f0acc8 100644
--- a/backends/cbackend.py
+++ b/backends/cbackend.py
@@ -1,7 +1,7 @@
 import sympy as sp
 from collections import namedtuple
 from sympy.core import S
-from typing import Optional, Set
+from typing import Set
 
 try:
     from sympy.printing.ccode import C99CodePrinter as CCodePrinter