[docs] [issue23406] interning and list comprehension leads to unexpected behavior

[Steven D'Aprano]

Steven D'Aprano added the comment:

Which note are you referring to? There are at least two mentioned in 
this thread, the FAQ and a footnote in the docs for stdtypes.

If you're referring to the table of operations just below these:

https://docs.python.org/2/library/stdtypes.html#sequence-types-str-unicode-list-tuple-bytearray-buffer-xrange

https://docs.python.org/3/library/stdtypes.html#common-sequence-operations

where the docs say:

	s * n, n * s	n shallow copies of s concatenated

I think that could be worded better. It is too easy to misread it 
as saying that the items of s are copied (as I just did now, despite 
knowing that they aren't). I would word it:

	repeat s n times and concatenate

which matches the common name of * as the sequence repetition operator, 
and avoids using the word prone to misinterpretation, "copy".

Given how error-prone sequence repetition is, I'd add an example 
directly in the table:

for example, [x]*3 returns [x, x, x] (note that x is not copied).

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