diff --git a/tests/README.md b/tests/README.md
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+++ b/tests/README.md
@@ -0,0 +1 @@
+pytest gathers tests according to a naming convention. By default any file that is to contain tests must be named starting with test_ and any function in a file that should be treated as a test must also start with test_.
diff --git a/tests/__init.py__ b/tests/__init.py__
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_example.py b/tests/test_example.py
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+++ b/tests/test_example.py
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+import pytest
+
+@pytest.mark.parametrize("test_input,expected", [
+    ("3+5", 8),
+    ("2+4", 6),
+    ("6*9", 42),
+])
+def test_eval(test_input, expected):
+    assert eval(test_input) == expected
+
+@pytest.mark.parametrize("test_input,expected", [
+    ("3+5", 8),
+    ("2+4", 6),
+    ("6*5", 30),
+])
+def test_eval2(test_input, expected):
+    assert eval(test_input) == expected