diff --git a/mitmproxy/README.md b/mitmproxy/README.md
index 7fbbf4d..abffb20 100644
--- a/mitmproxy/README.md
+++ b/mitmproxy/README.md
@@ -1,3 +1,21 @@
+# `dump.py`
+```python
+I = lambda module: __import__('importlib').import_module(module)
+
+def request(flow):
+    with I('dbm.sqlite3').open('dbm.sql') as db:
+        if (url := flow.request.url) in db:
+            flow.response = I('mitmproxy.http').Response.make(200, db[url])
+
+def response(flow):
+    if flow.response.status_code == 200:
+        with I('dbm.sqlite3').open('dbm.sql', 'c') as db:
+            db[flow.request.url] = flow.response.content
+
+if __name__ == '__main__':
+    I('subprocess').run(['mitmdump', '-s', __file__])
+```
+
 # Retries if failed
 ```python
 def response(flow):