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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 bulk_upsert(self, docs, namespace, timestamp):
 """Update or insert multiple documents into Solr docs may be any iterable """

        if self.auto_commit_interval is not None:
            add_kwargs = {
                "commit": (self.auto_commit_interval == 0),
                "commitWithin": str(self.auto_commit_interval)
            }
        else:
            add_kwargs = {"commit": False}

        cleaned = (self._clean_doc(d, namespace, timestamp) for d in docs)
        if self.chunk_size > 0:
            batch = list(next(cleaned) for i in range(self.chunk_size))
            while batch:
                self.solr.add(batch, **add_kwargs)
                batch = list(next(cleaned)
                             for i in range(self.chunk_size))
        else:
            self.solr.add(cleaned, **add_kwargs)