`utilities.iterables.iterable(Naturals)` returns `True` even though it's infinite.

https://github.com/sympy/sympy/blob/580478123816a986b27d27f379ad3d0482af2c82/sympy/utilities/iterables.py#L3026-L3030

```
In [15]: from sympy.utilities.iterables import iterable

In [16]: iterable(Naturals)
Out[16]: True

In [17]: solveset(sin(x))
Out[17]: {2⋅n⋅π │ n ∊ ℤ} ∪ {2⋅n⋅π + π │ n ∊ ℤ}

In [18]: iterable(_)
Out[18]: True
```

Insufficient checking in `function_range` can lead to an infinite loop:
https://github.com/sympy/sympy/blob/580478123816a986b27d27f379ad3d0482af2c82/sympy/calculus/util.py#L267-L272
(For a PR I'm working on I'm hitting this issue with a `Union` of `ImageSets`. I'll improve the check, but I may leave a more complete fix for later.)

	def iterable(i, exclude=(str, dict, NotIterable)):
	"""
	Return a boolean indicating whether ``i`` is SymPy iterable.
	True also indicates that the iterator is finite, e.g. you can
	call list(...) on the instance.

	if not iterable(solution):
	raise NotImplementedError(
	'Unable to find critical points for {}'.format(f))
	if isinstance(solution, ImageSet):
	raise NotImplementedError(
	'Infinite number of critical points for {}'.format(f))

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`utilities.iterables.iterable(Naturals)` returns `True` even though it's infinite. #25992

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utilities.iterables.iterable(Naturals) returns True even though it's infinite. #25992

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