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xarray/core/dataset.py

@@ -309,6 +309,7 @@ def _maybe_chunk(
             # when rechunking by different amounts, make sure dask names change
             # by providing chunks as an input to tokenize.
             # subtle bugs result otherwise. see GH3350
+            # we use str() for speed, and use the name for the final array name on the next line
             token2 = tokenize(token if token else var._data, str(chunks))
             name2 = f"{name_prefix}{name}-{token2}"