There is a code example about the set type found under:
https://docs.python.org/3/tutorial/datastructures.html

It reads as:
```
>>> basket = {'apple', 'orange', 'apple', 'pear', 'orange', 'banana'}
>>> print(basket)                      # show that duplicates have been removed
{'orange', 'banana', 'pear', 'apple'}
>>> 'orange' in basket                 # fast membership testing
True
>>> 'crabgrass' in basket
False

>>> # Demonstrate set operations on unique letters from two words
...
>>> a = set('abracadabra')
>>> b = set('alacazam')
>>> a                                  # unique letters in a
{'a', 'r', 'b', 'c', 'd'}
>>> a - b                              # letters in a but not in b
{'r', 'd', 'b'}
>>> a | b                              # letters in either a or b
```

I read "either a or b" as "a .EXOR. b". Shouldn't it be:
```
>>> a | b                              # letters in a or b
```
I don't speak English as a native language, so perhaps I am wrong.

ISTM the result of the expression makes the meaning clear:

    >>> a | b
    {'r', 'l', 'b', 'c', 'z', 'd', 'a', 'm'}

That said, the text might be a little clearer like this:

   # letters in a or b or both

English 'or' remains ambiguous, and often exclusive, even without 'either'.  Hence jokes like
  Parent: "Cake or pie?"
  Smart kid: "Both!"
I agree with replacing 'either' with 'or both'.

New changeset ca816153445cba3baec15f7e890c71abfe495340 by Mariatta (KatherineMichel) in branch 'master':
bpo-30312: Small correction in datastructures set code sample (GH-2081)
https://github.com/python/cpython/commit/ca816153445cba3baec15f7e890c71abfe495340

New changeset 865ed9ea67cf0d8a8dead91f3eac527553d92284 by Mariatta (KatherineMichel) in branch '3.6':
bpo-30312: Small correction in datastructures set code sample (GH-2081) (GH-2085)
https://github.com/python/cpython/commit/865ed9ea67cf0d8a8dead91f3eac527553d92284

Documentation has been updated, and backported to 3.6.
Thanks :)