[tutorial] Add ord tutorial

**Description of the tutorial**
... Python built-in function ord()

**Do you want to be assigned to work on this?**
(mark [x])
- [x] YES
- [ ] NO

**Optional: Any additional info you want to add**
...

Start by reviewing the repository's existing beginner tutorials and the Python built-in ord() documentation. Done means a new tutorial about ord() is added using the project's established tutorial format and explains the function for beginners.

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