Here's an improved version of the Python code:

Formatting the X-Axis to Show Every Year on Major Ticks with Matplotlib

How to Calculate Expected Values with Time Intervals: A Step-by-Step Guide

Improving Cosine Similarity Performance for Large Datasets Using Optimized Data Structures and Algorithms

Here's a refactored version of the code with proper indentation, comments, and a clear structure:

Understanding Python Multithreading: A Deep Dive into Threads, Synchronization, and Best Practices for Efficient Concurrency

Grouping Items by Classes Bounded by a Difference Less Than 4 Using Pandas and Data Mining Algorithms

I can help you with that. Here is a complete example of how you can implement data normalization using self-attention-based graph neural networks in Python:

Avoiding the Boolean Series Key Reindex Warning: A Flexible Filter Approach Using Groupby and Reduce

Calculating Mean of Classes by Groups of Rows and Columns in a Pandas DataFrame