diff --git a/python/pycrdt/_doc.py b/python/pycrdt/_doc.py
index c56d0b1..66a92bf 100644
--- a/python/pycrdt/_doc.py
+++ b/python/pycrdt/_doc.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Callable, Type, cast
+from typing import Callable, Type, TypeVar, cast
 
 from ._base import BaseDoc, BaseType, base_types
 from ._pycrdt import Doc as _Doc
@@ -8,6 +8,8 @@
 from ._pycrdt import Transaction as _Transaction
 from ._transaction import ReadTransaction, Transaction
 
+T_BaseType = TypeVar("T_BaseType", bound=BaseType)
+
 
 class Doc(BaseDoc):
     def __init__(
@@ -73,7 +75,7 @@ def __getitem__(self, key: str) -> BaseType:
     def __iter__(self):
         return iter(self.keys())
 
-    def get(self, key: str, *, type: Type[BaseType]) -> BaseType:
+    def get(self, key: str, *, type: Type[T_BaseType]) -> T_BaseType:
         value = type()
         self[key] = value
         return value