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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 keyrange's state as a dict. :rtype: dict :returns: state of this instance. """

        mapping = {}

        if self.start_open:
            mapping["start_open"] = self.start_open

        if self.start_closed:
            mapping["start_closed"] = self.start_closed

        if self.end_open:
            mapping["end_open"] = self.end_open

        if self.end_closed:
            mapping["end_closed"] = self.end_closed

        return mapping