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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def detokenize(s):
 """ Detokenize a string by removing spaces before punctuation."""

    print(s)
    s = re.sub("\s+([;:,\.\?!])", "\\1", s)
    s = re.sub("\s+(n't)", "\\1", s)
    return s