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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 snapshot(self, file_obj):
 """Take a snapshot of the database. :param file_obj: A file-like object to write the database contents in. """

        snapshot_request = etcdrpc.SnapshotRequest()
        snapshot_response = self.maintenancestub.Snapshot(
            snapshot_request,
            self.timeout,
            credentials=self.call_credentials,
            metadata=self.metadata
        )

        for response in snapshot_response:
            file_obj.write(response.blob)