**Is your feature request related to a problem? Please describe.** There are currently no automated tests for `util.py`, making it difficult to ensure that the utility functions work as intended and to catch regressions during development. **Describe 1~3 use cases of the purposed feature** - Verify that functions like `unix_time`, `cleanup_input`, `merge`, and `load_config` behave correctly for a variety of input values and edge cases. - Ensure that `parse_infobox` correctly parses infobox templates from page text and handles different contest configurations. - Confirm that error handling and logging for malformed input, missing configuration, or unusual Unicode/control characters works as intended. **Describe alternatives you've considered** - Relying on manual testing or indirect coverage through higher-level tests, but this does not guarantee that all code paths in `util.py` are exercised. - Adding only integration tests, which may not catch issues specific to the utility logic and infobox parsing. **Additional context** Unit tests for `util.py` will help maintain code quality and reliability. Tests could be implemented using pytest or unittest, and should cover both typical and edge-case usage of the utility functions.