https://www.py4e.com/lessons/strings
https://runestone.academy/ns/books/published/py4e-int/strings/toctree.html
https://www.keithdillon.com/index.php/python-for-data-science-spring-2026/
GitHub Classroom: https://classroom.github.com/classrooms/250035910-keithops-bds754-s26
Google CoLab: https://colab.research.google.com/notebooks/welcome.ipynb
7.1. A string is a sequence
https://runestone.academy/ns/books/published/py4e-int/strings/sequence.html
fruit = 'banana'
letter = fruit[1]
print(letter)
a
fruit[1] = 'b' # what does this do?
