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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 _addProteins(self, proteinIds, containerNames):
 """Add one or multiple proteinIds to the respective container. :param proteinIds: a proteinId or a list of proteinIds, a proteinId must be a string. :param containerNames: list, entries must be one or multiple of 'leading', 'subset', 'subsumableProteins' or 'proteins' :param addToProteins: bool, if True the proteinIds are added to the """

        proteinIds = AUX.toList(proteinIds)
        for containerName in containerNames:
            proteinContainer = getattr(self, containerName)
            proteinContainer.update(proteinIds)