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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 fullselection(self) -> selectiontools.Selection: """A |Selection| object containing all |Element| and |Node| objects defined by |XMLInterface.selections| and |XMLInterface.devices|. Selection("fullselection", nodes=("dill", "lahn_2", "lahn_3"), elements=("land_dill", "land_lahn_1", "land_lahn_2", "land_lahn_3")) """

        fullselection = selectiontools.Selection('fullselection')
        for selection in self.selections:
            fullselection += selection
        fullselection += self.devices
        return fullselection