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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 iter_links(self):
 """An iterator over the working links in the machine. Generates a series of (x, y, link) tuples. """

        for x in range(self.width):
            for y in range(self.height):
                for link in Links:
                    if (x, y, link) in self:
                        yield (x, y, link)