diff --git a/examples/addons/commands-paths.py b/examples/addons/commands-paths.py
index f37a0fbc5..4d9535b92 100644
--- a/examples/addons/commands-paths.py
+++ b/examples/addons/commands-paths.py
@@ -20,9 +20,9 @@ class MyAddon:
         for f in flows:
             totals[f.request.host] = totals.setdefault(f.request.host, 0) + 1
 
-        fp = open(path, "w+")
-        for cnt, dom in sorted([(v, k) for (k, v) in totals.items()]):
-            fp.write("%s: %s\n" % (cnt, dom))
+        with open(path, "w+") as fp:
+            for cnt, dom in sorted([(v, k) for (k, v) in totals.items()]):
+                fp.write("%s: %s\n" % (cnt, dom))
 
         ctx.log.alert("done")
 
diff --git a/mitmproxy/addons/session.py b/mitmproxy/addons/session.py
index 63e382ece..f9073c3e8 100644
--- a/mitmproxy/addons/session.py
+++ b/mitmproxy/addons/session.py
@@ -87,8 +87,8 @@ class SessionDB:
 
     def _create_session(self):
         script_path = pkg_data.path("io/sql/session_create.sql")
-        qry = open(script_path, 'r').read()
-        self.con.executescript(qry)
+        with open(script_path, 'r') as qry:
+            self.con.executescript(qry.read())
         self.con.commit()
 
     @staticmethod
diff --git a/mitmproxy/contrib/wbxml/ASCommandResponse.py b/mitmproxy/contrib/wbxml/ASCommandResponse.py
index 2d60eb2da..34755cbe6 100644
--- a/mitmproxy/contrib/wbxml/ASCommandResponse.py
+++ b/mitmproxy/contrib/wbxml/ASCommandResponse.py
@@ -63,8 +63,9 @@ if __name__ == "__main__":
 	listOfSamples = os.listdir(samplesDir)
 
 	for filename in listOfSamples:
-		byteWBXML = open(samplesDir + os.sep + filename, "rb").read()
-		
+		with open(samplesDir + os.sep + filename, "rb") as f:
+			byteWBXML = f.read()
+
 		logging.info("-"*100)
 		logging.info(filename)
 		logging.info("-"*100)
diff --git a/test/bench/benchmark.py b/test/bench/benchmark.py
index 84ec6005a..076ad6c9d 100644
--- a/test/bench/benchmark.py
+++ b/test/bench/benchmark.py
@@ -31,7 +31,8 @@ class Benchmark:
             stdout=asyncio.subprocess.PIPE
         )
         stdout, _ = await traf.communicate()
-        open(ctx.options.benchmark_save_path + ".bench", mode="wb").write(stdout)
+        with open(ctx.options.benchmark_save_path + ".bench", mode="wb") as f:
+            f.write(stdout)
         ctx.log.error("Proxy saw %s requests, %s responses" % (self.reqs, self.resps))
         ctx.log.error(stdout.decode("ascii"))
         backend.kill()
diff --git a/test/mitmproxy/addons/test_session.py b/test/mitmproxy/addons/test_session.py
index 20feb69d7..973514267 100644
--- a/test/mitmproxy/addons/test_session.py
+++ b/test/mitmproxy/addons/test_session.py
@@ -68,7 +68,8 @@ class TestSession:
             os.remove(path)
         con = sqlite3.connect(path)
         script_path = pkg_data.path("io/sql/session_create.sql")
-        qry = open(script_path, 'r').read()
+        with open(script_path) as f:
+            qry = f.read()
         with con:
             con.executescript(qry)
             blob = b'blob_of_data'