<s>[INST] Reverse a string in Python There is no built in reverse function in Python's str object. What is the best way of implementing this?
If supplying a very concise answer, please elaborate on it's efficiency. Is the str converted to a different object, etc. 
 [/INST] How about:
>>> 'hello world'[::-1]
'dlrow olleh'

This is extended slice syntax. It works by doing [begin:end:step] - by leaving begin and end off and specifying a step of -1, it reverses a string.
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