qiskit.transpiler needs function & class examples

[nonhermitian]

What is the expected enhancement?

[jakelishman]

While there's always more documentation that could be written, after #4134 this documentation has rather more content than it did when the issue was created.

If somebody were to extend this, good things to add would be:

• tweak the introduction to actually talk about qiskit.transpile and include a cross reference to it
• update the current text which is out-of-date (the part about layout passes, for one)
• talk about how to create a custom pass manager with the current set-up (Add StagedPassManager class for pass manager with defined stages #6403 notwithstanding)
• more prominently link to the list of passes qiskit.transpiler.passes

[joeswashington]

Hey I am looking for a good first issue to work on. Is this still needed? If so can I be assigned to it?

[mtreinish]

I'm not sure this issue is still relevant in the last couple of releases we've updated and improved the top level transpiler documentation quite a bit since the last comment ~1.5 yrs ago: https://qiskit.org/documentation/apidoc/transpiler.html (see #9087 for the details of those improvements). So I think that I'm going to close this issue as not being relevant anymore.

That being said @joeswashington if you look at the content on that page and see anything that you think needs improvement please feel free to comment here and we can reopen this issue. Or also just open a pull request with any changes you would like to make to the documentation and we can discuss them there too.