Race condition when initialzing p5

[JohnEdChristensen]

I ran into an error when initialzing p5 with Sketch()
pyodide.ffi.JsException: TypeError: defaultCanvas0.canvas is undefined

from proceso import Sketch

p5 = Sketch()

It comes from binding.py

    def __init__(self, id: str = "defaultCanvas0"):
        import js
        from pyodide.code import run_js

        self.id = id
        remove_sketch(self.id)
        create_sketch = f"var {self.id} = " + "new p5(() => { });"
        run_js(create_sketch)
        set_canvas_id = f"{self.id}.canvas.setAttribute('id', '{self.id}');"
        run_js(set_canvas_id)
        self._p5js = getattr(js.window, self.id)
        self._init_constants()
        self._update_system_variables()

attempting to access the canvas on the p5 instance that was just initiated can sometimes fail if p5 takes a bit too long to initialize.

I ran into this when also importing p5 sound

  <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.7.0/p5.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.4.0/addons/p5.sound.min.js"></script>

I think the addon might make p5 take longer than normal and exposes this problem.

Reproduction:
Starting from the starter template, load the p5js sound library, see crash on init.

example repo:
https://johnc14231.pyscriptapps.com/proceso-starter-copy-54206/

Suggested fix:
Wait till p5 initialization is complete before continuing setup. Not sure what the best approach is, since I don't see a "run_js_async" equivalent to "run_js". Maybe having some sort of callback that continues the python setup after p5 initialization.