Get indexes chosen when slicing a list

I have a list:

things = ["a", "b", "c", "d", "e", "f"]

I also have a slice object provided to me, intended for the list above. Here's an example:

s = slice(-2, None, None)
print(things[-2:])  # ['e', 'f']

My goal is to extract the specific indexes the slice impacts. In this example, that would be:

[4, 5]

Does anyone know how I would go about doing this more pythonically? My current solution is:

print([i for i in range(len(things))]
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)  # [4, 5]

This is exactly the purpose of the indices method of the slice class.

As explained in the built-in help:

Help on built-in function indices:

indices(...) method of builtins.slice instance
    S.indices(len) -> (start, stop, stride)
    
    Assuming a sequence of length len, calculate the start and stop
    indices, and the stride length of the extended slice described by
    S. Out of bounds indices are clipped in a manner consistent with the
    handling of normal slices.

Thus, pass it the length of the sequence that will be sliced, in order to get the corresponding start/stop/stride values:

>>> s = slice(-2, None, None)
>>> 
>>> things = ['a', 'b', 'c', 'd', 'e', 'f']
>>> things
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['e', 'f']
>>> s.indices(len(things))
(4, 6, 1)
>>> x, y, z = s.indices(len(things))
>>> things[x:y:z]
['e', 'f']

Which can of course be used to construct the corresponding range of values:

>>> list(range(*s.indices(len(things))))
[4, 5]

As an aside, range objects can be indexed and sliced directly, and converting them to lists is as easy as passing them directly to the list type. Thus:

>>> list(range(len(things))
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)
[4, 5]
>>> list(range(len(things)))
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[4, 5]

This is simpler for getting an actual list of indices; in other contexts (for example, implementing __getitem__ for a custom type) the start/stop/stride values may be more directly useful.