Add unit tests for calculator

calculator/lib/python3.12/site-packages/flake8/main/cli.py

@@ -0,0 +1,24 @@
+"""Command-line implementation of flake8."""
+from __future__ import annotations
+
+import sys
+from collections.abc import Sequence
+
+from flake8.main import application
+
+
+def main(argv: Sequence[str] | None = None) -> int:
+    """Execute the main bit of the application.
+
+    This handles the creation of an instance of :class:`Application`, runs it,
+    and then exits the application.
+
+    :param argv:
+        The arguments to be passed to the application for parsing.
+    """
+    if argv is None:
+        argv = sys.argv[1:]
+
+    app = application.Application()
+    app.run(argv)
+    return app.exit_code()