diff --git a/src/fancymath/math.py b/src/fancymath/math.py
index 30f3ea8..eafeaf8 100644
--- a/src/fancymath/math.py
+++ b/src/fancymath/math.py
@@ -12,4 +12,11 @@ def fact(n: int) -> int:
     if n == 1:
         return 1
     else:
-        return n * fact(n - 1)
\ No newline at end of file
+        return n * fact(n - 1)
+
+
+if __name__ == '__main__':
+    n = 5
+    assert fact(n) == 120
+    assert add(5, 6) == 11
+    print("Tests passed")
\ No newline at end of file