Python - converting a list of tuples to a list of strings
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I have a list of tuples that looks like this:

    [('this', 'is'), ('is', 'the'), ('the', 'first'), ('first', 'document'), ('document', '.')]

What is the most pythonic and efficient way to convert into this where each token is separated by a space:

['this is', 'is the' 'the first', 'first document', 'document .']