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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 is_build_needed(self, data_sink, data_src):
 """ returns true if data_src needs to be rebuilt, given that data_sink has had a rebuild requested. """

        return (self._gettask(data_src).last_build_time == 0 or
                self._gettask(data_src).last_build_time <
                self._gettask(data_sink).last_build_time)