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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 return_tip(self, home_after=True):
 """ Drop the pipette's current tip to it's originating tip rack Notes ----- This method requires one or more tip-rack :any:`Container` to be in this Pipette's `tip_racks` list (see :any:`Pipette`) Returns ------- This instance of :class:`Pipette`. Examples -------- .. """

        if not self.tip_attached:
            log.warning("Cannot return tip without tip attached.")

        if not self.current_tip():
            self.robot.add_warning(
                'Pipette has no tip to return, dropping in place')

        self.drop_tip(self.current_tip(), home_after=home_after)
        return self