Here is the complete code with all the examples:

Optimizing Entity Counting: A Numpy Broadcasting Approach

Understanding Scatter Plots and Resolving the "ValueError: x and y must be the same size" Error When Creating a Scatter Plot with Matplotlib

Pandas Pivot Table Aggregation: Understanding the TypeError and Correct Solutions

Merging Columns into a Row and Making Column Values into New Columns with Pandas: A Step-by-Step Guide

Achieving Parallel Indexing in Pandas Panels for Efficient Data Analysis

Exploding a Column of Objects in Pandas DataFrames: A Comprehensive Guide

The problem is that you're trying to append data to `final_dataframe` using `_append`, which doesn't work because it's not designed for appending rows.

Merging Columns and Filling Empty Space with Pandas Python

Efficiently Generating a Date Range DataFrame with Pandas Iterrows Method