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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:
 async def drop_tip(self, mount, home_after=True):
 """ Drop tip at the current location :param Mount mount: The mount to drop a tip from :param bool home_after: Home the plunger motor after dropping tip. This is used in case the plunger motor skipped while dropping the tip, and is also used to recover the ejector shroud after a drop. """

        instr = self._attached_instruments[mount]
        assert instr
        assert instr.has_tip, 'Cannot drop tip without a tip attached'
        self._log.info("Dropping tip off from {}".format(instr.name))
        plunger_ax = Axis.of_plunger(mount)
        droptip = instr.config.drop_tip
        bottom = instr.config.bottom
        self._backend.set_active_current(plunger_ax,
                                         instr.config.plunger_current)
        await self._move_plunger(mount, bottom)
        self._backend.set_active_current(plunger_ax,
                                         instr.config.drop_tip_current)
        await self._move_plunger(
            mount, droptip, speed=instr.config.drop_tip_speed)
        await self._shake_off_tips(mount)
        self._backend.set_active_current(plunger_ax,
                                         instr.config.plunger_current)
        instr.set_current_volume(0)
        instr.remove_tip()
        if home_after:
            safety_margin = abs(bottom-droptip)
            async with self._motion_lock:
                smoothie_pos = self._backend.fast_home(
                    plunger_ax.name.upper(), safety_margin)
                self._current_position = self._deck_from_smoothie(smoothie_pos)
            await self._move_plunger(mount, safety_margin)