Issue 14: now has a Duck class!

[richelbilderbeek]

It is just the start :duck:

Fix #14

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (16287c2) 91.20% compared to head (740c220) 91.60%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #19 +/- ## =========================================== + Coverage 91.20% 91.60% +0.40% =========================================== Files 3 5 +2 Lines 125 131 +6 =========================================== + Hits 114 120 +6 Misses 11 11 ``` | [Flag](https://app.codecov.io/gh/programming-formalisms/programming_formalisms_project_autumn_2023/pull/19/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=None) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/programming-formalisms/programming_formalisms_project_autumn_2023/pull/19/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=None) | `91.60% <100.00%> (+0.40%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=None#carryforward-flags-in-the-pull-request-comment) to find out more.

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[richelbilderbeek]

Please ignore the code coverage test. I will promise I will do better in the future.

[richelbilderbeek]

Done! Thanks @AlexFHart for the review!