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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 first(self, **kwargs):
 """ Retrieve the first node from the set matching supplied parameters :param kwargs: same syntax as `filter()` :return: node """

        result = result = self._get(limit=1, **kwargs)
        if result:
            return result[0]
        else:
            raise self.source_class.DoesNotExist(repr(kwargs))