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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 derive_depth(self, depth):
 """Derives a new event from this one setting the ``depth`` attribute. Args: depth: (int):
 The annotations associated with the derived event. Returns: IonEvent: The newly generated event. """

        cls = type(self)
        # We use ordinals to avoid thunk materialization.
        return cls(
            self[0],
            self[1],
            self[2],
            self[3],
            self[4],
            depth
        )