improvements in text

[kamil-kaczmarek]

Signed-off-by: Kamil A. Kaczmarek kaczmarek.poczta@gmail.com

Changes summary

text fixes, performance only in summary, better names for sections

PR scope

• [ ] new notebook
• [x] improvements to the existing notebook
• [ ] bug fixes
• [ ] other

Checklist

• [x] notebook is without outputs
• [x] empty cells are removed
• [x] code is formatted with black
• [x] imports are sorted
• [ ] if new notebook is added, README is updated