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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 read_data_transition(self, length, whence=None, skip=False, stream_event=ION_STREAM_INCOMPLETE_EVENT):
 """Returns an immediate event_transition to read a specified number of bytes."""

        if whence is None:
            whence = self.whence

        return Transition(
            None, _read_data_handler(length, whence, self, skip, stream_event)
        )