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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, lock=False):
 """Create a snapshot of latest objects in bucket. :param lock: Create the new bucket in a locked state. :returns: Newly created bucket containing copied ObjectVersion. """

        with db.session.begin_nested():
            bucket = Bucket(
                default_location=self.default_location,
                default_storage_class=self.default_storage_class,
                quota_size=self.quota_size,
            )
            db.session.add(bucket)

        for o in ObjectVersion.get_by_bucket(self):
            o.copy(bucket=bucket)

        bucket.locked = True if lock else self.locked

        return bucket