diff --git a/test_addon.py b/test_addon.py
new file mode 100644
index 0000000..eba535c
--- /dev/null
+++ b/test_addon.py
@@ -0,0 +1,10 @@
+from mitmproxy.http import HTTPFlow
+
+
+def requestheaders(flow: HTTPFlow) -> None:
+    host = flow.request.pretty_host
+    flow.request.host = '127.0.0.1'
+    flow.request.port = 4001
+    flow.request.headers['X-Forwarded-Proto'] = flow.request.scheme
+    flow.request.scheme = 'http'
+    flow.request.host_header = host