Matching codes and merging dataframes with duplicates: A pandas solution using .map()

Merging Two Dataframes with a Bit of Slack Using pandas merge_asof Function

Resolving TypeErrors in Pandas Merges: Understanding and Converting List-Based Column Values.

Merging Multiple Data Frames in R: A Comprehensive Guide

Merging Dataframes with Non-Existing Columns: A Comprehensive Guide to Outer Joins in Pandas

Merging DataFrames in Python: A Step-by-Step Guide

Performing Nearest Value Lookup Involving Categorical Groupings with Pandas in Python

Merging DataFrames with Trailing Path Elements Using Regular Expressions and String Manipulation Techniques

Here is a complete code snippet that combines all the interleaved code you wrote in a nice executable codeblock:

Troubleshooting Pandas Left Join Results in Empty Values When Data Types Don’t Match