diff --git a/python-temel/class.sample.foo.py b/python-temel/class.sample.foo.py
new file mode 100644
index 0000000..b61b8d4
--- /dev/null
+++ b/python-temel/class.sample.foo.py
@@ -0,0 +1,14 @@
+class Sample:
+    def __init__(self, a, b):
+        self.a = a
+        self.b = b
+
+def foo(k):
+    print(k.a, k.b)                  # 10 20
+    k.a = 100
+    k.b = 200
+
+s = Sample(10, 20)
+print(s.a, s.b)                      # 10 20
+foo(s)
+print(s.a, s.b)                      # 100 200