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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 getActors(self, obj=None, renderer=None):
 """ Return an actors list. If ``obj`` is: ``None``, return actors of current renderer ``int``, return actors in given renderer number ``vtkAssembly`` return the contained actors ``string``, return actors matching legend name :param int,vtkRenderer renderer: specify which renederer to look into. """

        if renderer is None:
            renderer = self.renderer
        elif isinstance(renderer, int):
                renderer = self.renderers.index(renderer)
        else:
            return []

        if obj is None or isinstance(obj, int):
            if obj is None:
                acs = renderer.GetActors()
            elif obj >= len(self.renderers):
                colors.printc("~timesError in getActors: non existing renderer", obj, c=1)
                return []
            else:
                acs = self.renderers[obj].GetActors()
            actors = []
            acs.InitTraversal()
            for i in range(acs.GetNumberOfItems()):
                a = acs.GetNextItem()
                if a.GetPickable():
                    r = self.renderers.index(renderer)
                    if a == self.axes_exist[r]:
                        continue
                    actors.append(a)
            return actors

        elif isinstance(obj, vtk.vtkAssembly):
            cl = vtk.vtkPropCollection()
            obj.GetActors(cl)
            actors = []
            cl.InitTraversal()
            for i in range(obj.GetNumberOfPaths()):
                act = vtk.vtkActor.SafeDownCast(cl.GetNextProp())
                if act.GetPickable():
                    actors.append(act)
            return actors

        elif isinstance(obj, str):  # search the actor by the legend name
            actors = []
            for a in self.actors:
                if hasattr(a, "_legend") and obj in a._legend:
                    actors.append(a)
            return actors

        elif isinstance(obj, vtk.vtkActor):
            return [obj]

        if self.verbose:
            colors.printc("~lightning Warning in getActors: unexpected input type", obj, c=1)
        return []