"Mutable and Immutable Types" example

The best example in the Mutable and Immutable Types section of the Structuring Your Project page is:

# create a concatenated string from 0 to 19 (e.g. "012..1819")
nums = [str(n) for n in range(20)]
print "".join(nums)

It is considered the best example for being both more efficient and succinct.

Would this be a better example to use?

''.join(map(str, range(20)))

It's more succinct and is faster:

$ python -m timeit "nums = [str(n) for n in range(20)]; ''.join(nums)"
100000 loops, best of 3: 6.84 usec per loop

$ python -m timeit "''.join(map(str, range(20)))"
100000 loops, best of 3: 4.93 usec per loop

リンク先の「Structuring Your Project」ページの「Mutable and Immutable Types」セクションから始め、既存の例と提案された式を比較してください。ドキュメントが合意された例を使用し、パフォーマンスに関する主張を正確に提示していれば完了です。