[::-1] is an idiomatic way to reverse a string in Python that is the obvious way for a habitual user of the language to do it e.g.:
def palindrome(s):
return s == s[::-1]
It could be discussed whether ''.join(reversed(s)) is more readable for a novice programmer learning Python. In general, Python prefers words over punctuation.
Also, there are objects that can be reversed() that are not sequences.
I considered using the [::-1] syntax to reverse the list, but decided that there was enough "cute" stuff in the examples already.