diff --git a/icecream/icecream.py b/icecream/icecream.py
index a27fd14..aac1de0 100644
--- a/icecream/icecream.py
+++ b/icecream/icecream.py
@@ -140,7 +140,7 @@ def get_text_with_indentation(self, node):
 
 
 def prefixLines(prefix, s, startAtLine=0):
-    # type: (str, str, int) -> list[str]
+    # type: (str, str, int) -> List[str]
     lines = s.splitlines()
 
     for i in range(startAtLine, len(lines)):