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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 suggestions(self,index=None):
 """Get suggestions for correction. Yields: :class:`Suggestion` element that encapsulate the suggested annotations (if index is ``None``, default) Returns: a :class:`Suggestion` element that encapsulate the suggested annotations (if index is set) Raises: :class:`IndexError` """

        if index is None:
            return self.select(Suggestion,None,False, False)
        else:
            for i, e in enumerate(self.select(Suggestion,None,False, False)):
                if index == i:
                    return e
            raise IndexError