CrowdStrike's blog post details the transition from Python 2 to Python 3 within their data science team, highlighting the challenges and strategies involved in upgrading approximately 200,000 lines of code. The post emphasizes the importance of management support, cataloging code dependencies, and utilizing automation tools like Tox, Futurize, and Six to facilitate the transition. The team faced significant hurdles in maintaining code functionality, especially in complex feature extractors used for machine learning. They overcame these challenges by enhancing their testing suite with tools like pytest, leading to a substantial increase in test cases and improved code quality. The transition not only modernized their codebase but also provided greater insight into legacy code, preparing the team for more ambitious projects in the future. The blog underscores the broader benefits of upgrading, such as improved security, performance gains, and easier training and hiring processes, ultimately positioning the organization for long-term success.