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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 _make_dataset(cls, coords):
 """Construct a new dataset given the coordinates. """

        class Slice(cls._SliceType):
            extra_coords = coords

        Slice.__name__ = '%s.slice(%s)' % (
            cls.__name__,
            ', '.join('%s=%r' % item for item in coords.items()),
        )
        return Slice