Put the words of a sentence in alphabetical order.

Assignment

Write a function alphabetical to which a string must be passed as an argument. The string contains a sentence of which the words consist only of lowercase letters and are separated by a single space. There is no punctuation. The function should return a string in which the words from the given sentence are placed in alphabetical order, and are each separated by a single space.

Example

>>> alphabetical('roberta ran rings around the roman ruins')
'around ran rings roberta roman ruins the'

>>> alphabetical('six sleek swans swam swiftly southwards')
'six sleek southwards swam swans swiftly'