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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 to_dict(self):
 """Return a dictionary representation of the error. :return: A dict with the keys: - attr: Attribute which contains the error, or "<root>" if it refers to the schema root. - errors: A list of dictionary representations of the errors. """

        def exception_to_dict(e):
            try:
                return e.to_dict()
            except AttributeError:
                return {
                    "type": e.__class__.__name__,
                    "error": str(e),
                }

        result = {
            "errors": [exception_to_dict(e) for e in self.errors]
        }
        if self.index is not None:
            result["index"] = self.index
        else:
            result["attr"] = self.attr if self.attr is not None else "<root>"
        return result