diff --git a/src/adler/example_code.py b/src/adler/example_code.py
new file mode 100644
index 0000000..6db6520
--- /dev/null
+++ b/src/adler/example_code.py
@@ -0,0 +1,2 @@
+def test_function(x):
+    return x * x
diff --git a/tests/adler/test_example.py b/tests/adler/test_example.py
new file mode 100644
index 0000000..fda9c57
--- /dev/null
+++ b/tests/adler/test_example.py
@@ -0,0 +1,6 @@
+def test_test_function():
+    from adler.example_code import test_function
+
+    test_value = test_function(2)
+
+    assert test_value == 4