diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..a4e4a35
--- /dev/null
+++ b/tests/__init__.py
@@ -0,0 +1 @@
+import ziffers
\ No newline at end of file
diff --git a/tests/run_tests.py b/tests/run_tests.py
new file mode 100644
index 0000000..b69c9aa
--- /dev/null
+++ b/tests/run_tests.py
@@ -0,0 +1,13 @@
+import pytest
+from ziffers import *
+
+@pytest.mark.parametrize(
+    "pattern",
+    [
+        "1 2 3",
+        "(1 (2 3))"
+        "q 2 q2 eq.4"
+    ],
+)
+def test_list_arithmetic(pattern: str):
+    assert parse_expression(pattern).text == pattern
\ No newline at end of file
diff --git a/ziffers/__pycache__/__init__.cpython-311.pyc b/ziffers/__pycache__/__init__.cpython-311.pyc
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diff --git a/ziffers/__pycache__/parser.cpython-311.pyc b/ziffers/__pycache__/parser.cpython-311.pyc
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