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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 print_unfinished_line(self):
 """The unfinished line stayed long enough in the buffer to be printed"""

        if self.state is STATE_RUNNING:
            if not callbacks.process(self.read_buffer):
                self.print_lines(self.read_buffer)
            self.read_buffer = b''