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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_event(self, whence, complete=False, can_flush=False):
 """Creates a transition to a co-routine for retrieving data as bytes. Args: whence (Coroutine):
 The co-routine to return to after the data is satisfied. complete (Optional[bool]):
 True if STREAM_END should be emitted if no bytes are read or available; False if INCOMPLETE should be emitted in that case. can_flush (Optional[bool]):
 True if NEXT may be requested after INCOMPLETE is emitted as a result of this data request. """

        return Transition(None, _read_data_handler(whence, self, complete, can_flush))