diff --git a/responses/matchers.py b/responses/matchers.py
index 40f3a83d..905a9c3c 100644
--- a/responses/matchers.py
+++ b/responses/matchers.py
@@ -15,6 +15,7 @@
 from urllib.parse import urlparse
 
 from requests import PreparedRequest
+from requests.sessions import _Files
 from urllib3.util.url import parse_url
 
 
@@ -276,7 +277,7 @@ def match(request: PreparedRequest) -> Tuple[bool, str]:
 
 
 def multipart_matcher(
-    files: Mapping[str, Any], data: Optional[Mapping[str, str]] = None
+    files: _Files, data: Optional[Mapping[str, str]] = None
 ) -> Callable[..., Any]:
     """
     Matcher to match 'multipart/form-data' content-type.