[tutorial] f-strings in python

[mananuppadhyay]

Description of tutorial f-strings are easy to learn and save time while formatting strings, and hence are much more efficient than the other methods. I couldn't find a tutorial on the same and thought of making one. I'll try covering the following:

1. Syntax of f-strings
2. Multiple annotated examples of using them

Do you want to be assigned to work on this? (mark [x])

• [x] YES
• [ ] NO

[funbeedev]

@mananuppadhyay Thanks for the tutorial suggestion! I've assigned you now.

[mananuppadhyay]

I've made a PR. Please do let me know if there are any changes still required.