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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 unparse(self, pieces, defaults=None):
 """Join the parts of a URI back together to form a valid URI. pieces is a tuble of URI pieces. The scheme must be in pieces[0] so that the rest of the pieces can be interpreted. """

        return self.parser_for(pieces[0])(defaults).unparse(pieces)