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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 get_or_create(self, write_concern=None, auto_save=True, *q_objs, **query):
 """Retrieve unique object or create, if it doesn't exist. Returns a tuple of ``(object, created)``, where ``object`` is the retrieved or created object and ``created`` is a boolean specifying whether a new object was created. Taken back from: https://github.com/MongoEngine/mongoengine/ pull/1029/files#diff-05c70acbd0634d6d05e4a6e3a9b7d66b """

        defaults = query.pop('defaults', {})
        try:
            doc = self.get(*q_objs, **query)
            return doc, False
        except self._document.DoesNotExist:
            query.update(defaults)
            doc = self._document(**query)

            if auto_save:
                doc.save(write_concern=write_concern)
            return doc, True