provide Python function returning stringified dict component IDs

Is your feature request related to a problem? Please describe.
When you use pattern matching callbacks and component IDs of type dictionaries, Dash will automatically stringify the IDs before being sent to the browser/DOM.

As far as I know, even if you use the Dash pytest/selenium plugin, if you want to do certain tests on these components (and select them by ID), you would need to find out + assume how the dictionary ID → string ID conversion is done by Dash.

Describe the solution you'd like
A python function callable from somewhere in the dash package which does the conversion, and thereby can safely be used in tests of Dash apps, across dash versions. E.g. something like:

def stringify_id(dict_id: Dict[str, str]) -> str:
    ...


stringify_id({"id": "some_id", "type": "some_type"}) == '{\"id\"\:\"some_id\"\,\"type\"\:\"some_type\"\}'

Additional context
It looks like the conversion internally in Dash today is done on the JavaScript side:
https://github.com/plotly/dash/blob/597dc22c86de97530fb9b0a9bd9f7876bd0d7601/dash-renderer/src/actions/dependencies.js#L111-L123

One way of supporting the use case above would be to add a Python function doing the same stringify logic, and then add new selenium tests to the Dash test suite to ensure the Python-stringify = JavaScript-stringify. Can we do better? Or maybe there is already a solution for this use case (of testing elements with dict IDs) using e.g. dash_duo?

Start with dash-renderer/src/actions/dependencies.js at lines 111-123 to understand the existing browser-side conversion, then inspect the Dash test suite and dash_duo or Selenium coverage mentioned in the issue. Add a callable Python conversion entry point and tests demonstrating that its output matches the JavaScript behavior for dictionary component IDs.