Car Sales Analysis & Visualization

I’m providing a single CSV that contains the full history of our car sales—no date filtering is needed because I want every record in the file analysed.
Your task is to work in Python (Pandas for manipulation, Matplotlib or Seaborn for plotting) to:

• clean and prepare the data, filling or flagging any gaps
• run an exploratory analysis that pinpoints the top-performing car brands, shows how sales are distributed among sellers, and highlights which fuel types dominate overall
• create clear, publication-ready visuals (high resolution, labelled axes, readable legends) that communicate those three insights at a glance
• package everything in a fully reproducible Jupyter notebook or .py script with comments, plus the exported images and a short written summary of key takeaways.

I’ll consider the job complete when the notebook runs end-to-end on my machine, generates the same figures, and your summary accurately reflects the numbers in the plots.