diff --git a/cura/Utils/Decorators.py b/cura/Utils/Decorators.py
index 52f61eb1f5..9275ee6ce9 100644
--- a/cura/Utils/Decorators.py
+++ b/cura/Utils/Decorators.py
@@ -3,6 +3,7 @@
 
 import functools
 import re
+from typing import Callable
 
 # An API version must be a semantic version "x.y.z" where ".z" is optional. So the valid formats are as follows:
 #  - x.y.z
@@ -16,7 +17,7 @@ SEMANTIC_VERSION_REGEX = re.compile(r"^[0-9]+\.[0-9]+(\.[0-9]+)?$")
 #   \param since_version The earliest version since when this API becomes supported. This means that since this version,
 #                        this API function is supposed to behave the same. This parameter is not used. It's just a
 #                        documentation.
-def api(since_version: str) -> callable:
+def api(since_version: str) -> Callable:
     # Make sure that APi versions are semantic versions
     if not SEMANTIC_VERSION_REGEX.fullmatch(since_version):
         raise ValueError("API since_version [%s] is not a semantic version." % since_version)