Re-indent logpuzzle.py
Implement test_read_urls() to expect stubbed results, implement read_urls() to return a stub result so that test passes.
Implement test_is_puzzle_url() to expect stubbed results, implement is_puzzle_url() to return True so that test passes.
In test_logpuzzle.py add test_path_from_string(). In logpuzzle.py add path_from_string(), use it to implement is_puzzle_url()