Add two tests

app/app/calc.py

@@ -0,0 +1,7 @@
+# Calculator functions
+
+def add(x,y):
+    return x + y
+
+def subtract(x,y):
+    return x - y

app/app/tests.py

@@ -0,0 +1,15 @@
+# Sample test
+
+from django.test import SimpleTestCase
+
+from app import calc
+
+class CalcTests(SimpleTestCase):
+    # Test the calc module
+    def test_add_numbers(self):
+        res = calc.add(5, 6)
+        self.assertEqual(res, 11)
+
+    def test_subtract_numbers(self):
+        res = calc.subtract(10, 5)
+        self.assertEqual(res, 5)