added s examples.

solid/single_responsability/simple_function_test.py

@@ -0,0 +1,18 @@
+from solid.single_responsability.simple_function import get_user
+
+
+class TestGetUser:
+    def test_happy_path(self):
+        assert get_user("marie-eve") is None
+        assert get_user("walid").name == 'walid'
+
+    def test_admin(self):
+        assert get_user("tristan") is None
+        assert get_user("tristan", is_admin=True) is not None
+        assert get_user("tristan", is_admin=True).name == "tristan"
+
+    def test_old_users(self):
+        assert get_user("jonathan") is None
+        assert get_user("jonathan", is_admin=True) is None
+        assert get_user("jonathan", consider_old_users=True) is not None
+        assert get_user("jonathan", consider_old_users=True).name == "jonathan"