Add Python docstrings and reformat

🛠️ PR Summary

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Enhanced documentation and improved image handling in Flickr scraper and utility functions. 📸✨

Added detailed docstrings to functions, making the code easier to understand and use. 📝
Improved URL construction for fetching images from Flickr, ensuring more reliability in retrieving original size images. 🔗
Enhanced image processing in clean_images.py, including resizing, converting to JPG, and removing corrupt or duplicate files, with clearer documentation on functionality and arguments. 🖼️➕
Updated download_uri function with better error handling and support for additional image formats, increasing robustness. 🛠️
Introduced a function in multithread_example.py demonstrating how to download files with error handling, useful for learning about multithreading applications. 🧵

Purpose: These changes aim to make the Flickr scraper more efficient, user-friendly, and versatile in handling different image formats and downloading tasks. The addition of comprehensive documentation further aids developers and users in understanding and leveraging the tool's capabilities effectively.
Impact: Users will benefit from more reliable image fetching and processing, enabling better data collection for projects requiring image datasets. The clear documentation also lowers the entry barrier for new users or contributors, potentially increasing the tool's user base and contribution rate. These updates may also lead to improvements in image-based machine learning or data analysis projects by providing a more robust toolset for image acquisition and preprocessing. 🚀👥