issues: 1952739368

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id node_id number title user state locked assignee milestone comments created_at updated_at closed_at author_association active_lock_reason draft pull_request body reactions performed_via_github_app state_reason repo type
1952739368 PR_kwDOAMm_X85dTMKv 8339 Reduce dask tokenization time 6042212 closed 0     6 2023-10-19T17:22:06Z 2023-10-20T23:13:44Z 2023-10-20T23:13:43Z CONTRIBUTOR   0 pydata/xarray/pulls/8339

When using dask (e.g., chunks={} with a zarr dataset), each dask.array gets a token. Calculating this token currently hits a recursive path within dask and is relatively slow (~10ms), which adds up for many variables. This PR makes a simpler but still unique token.

An example profile of open_dataset before:

and after 

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