alxmrs opened a new issue, #24685:
URL: https://github.com/apache/beam/issues/24685

   ### What happened?
   
   To me, this is a really interesting corner case! Here's what's going on: 
   
   I'm updating an operator in XArray-Beam 
https://github.com/google/xarray-beam/pull/69. I have a type that I've defined 
as follows: 
   ```
   Chunk = Union[Tuple[Key, xarray.Dataset], Tuple[Key, Tuple[xarray.Dataset, 
...]]]
   ```
   In versions of Python before 3.10, this causes no problems. However, in 3.10 
(and presumably onward), this type leads to a error: 
   ```
   ValueError: expecting type typing.Tuple[xarray_beam._src.core.Key, 
xarray.core.dataset.Dataset] to have arity 0, had arity 2 instead
   ```
   
   I've looked a bit in depth at the sources, and I think this is the root 
cause of the issue: 
   
https://github.com/apache/beam/blob/4886bdf08fd057a0f8a4e99ab30453089654188d/sdks/python/apache_beam/typehints/native_type_compatibility.py#L108
   
   This function, which checks if the tuple has annotations to test if it's a 
named tuple, doesn't behave as I'd expect. In Python 3.10, it treats `Tuple` as 
a `NamedTuple` (which it is not). Further, when I change the type annotation to 
`tuple`, no errors occur. It seems like the recent addition of type-annotations 
with built-ins will require how `match_is_named_tuple` is implemented:
   
   - https://docs.python.org/3/library/typing.html#typing.Tuple
   - https://peps.python.org/pep-0585/
   
   As a workaround, users can use the `tuple` tuple annotation via 
`__futures__` for Python 3.7 and later.
   https://peps.python.org/pep-0585/#implementation
   
   ### Issue Priority
   
   Priority: 2 (default / most bugs should be filed as P2)
   
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