Add dunder methods tag

[Objectivitix]

Relevant Issues

Closes #1598.

Description

Adds the dunder methods tag described in that issue.

Sorry for the second to fourth commits, I forgot about good commit messages lol, so here they are

1. Add text to the tag explaining dunder methods
2. Add an example codeblock of __init__, __str__, and __repr__
3. Make the codeblock structured like a script instead of an interactive REPL session

[bast0006]

Thanks for taking the time to write this out, it's great. A chunk of these are just suggestions that could make it better rather than required changes, if you can't fit them feel free to just say so/let another reviewer look at it.

If you're curious, here's what it looks like in a testing environment at the moment: https://cdn.discordapp.com/attachments/476196003733569547/855567737653166140/dunder-method-test-1.png

[Xithrius]

@Objectivitix When creating a commit message, please make sure that if a person was to look back into git history they'd be able to get a hint of what occurred in a change/addition/deletion.

For more information on how to create a great commit message, see this tutorial.

[bast0006]

Looks good, just two last things

[Objectivitix]

@Xithrius thanks for telling me this. From now on, I'm putting all the changes in the extended description.

[Xithrius]

@Xithrius thanks for telling me this. From now on, I'm putting all the changes in the extended description.

I think this should only occur for commits that absolutely need more of an explanation. The message should be short enough to where it's not truncated by GitHub, and give a very quick insight to the change.

[Objectivitix]

@Xithrius got it

[Objectivitix]

All checks passed, exapoggers

[Objectivitix]

E X A P O G G E R S

[Objectivitix]

Thanks to everyone who reviewed!!