Add flake8 quality tests

Author: Smit-create

test/test_code_quality.py

@@ -0,0 +1,41 @@
+import subprocess
+import os
+import pathlib
+import shutil
+
+
+ROOT_DIR = pathlib.Path(os.path.abspath(__file__)).parents[1]
+LECTURE_DIR = os.path.join(ROOT_DIR, 'lectures')
+
+
+def check_unused_imports(py_files_dir):
+    # Use flake8 to check for unused imports (F401)
+    ret = subprocess.run(['flake8', '--select', 'F401', py_files_dir],
+                         stdout=subprocess.PIPE)
+    if ret.returncode != 0:
+        print(ret.stdout.decode('utf-8'))
+        raise Exception("Please remove the unused imports")
+    print("Passed: Code Quality tests")
+
+
+if __name__ == "__main__":
+    test_dir = os.path.join(ROOT_DIR, '__test_code_quality_tmp')
+    if not os.path.exists(test_dir):
+        os.makedirs(test_dir)
+
+    for file_name in os.listdir(LECTURE_DIR):
+        if file_name.endswith(".md"):
+            base_file_name = pathlib.Path(file_name).stem
+            cmd = ["jupytext", "--to", "py",
+                f"lectures/{file_name}", "-o",
+                f"{test_dir}/{base_file_name}.py"]
+            ret = subprocess.run(cmd, stdout=subprocess.PIPE)
+            if ret.returncode != 0:
+                shutil.rmtree(test_dir)
+                print(ret.stdout.decode('utf-8'))
+                raise Exception(f"jupytext failed for file {file_name}")
+
+    try:
+        check_unused_imports(test_dir)
+    finally:
+        shutil.rmtree(test_dir)