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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 loadFiles(self, fileNames, rtiClass=None):
 """ Loads files into the repository as repo tree items of class rtiClass. Auto-detects using the extensions when rtiClass is None """

        for fileName in fileNames:
            self.repo.loadFile(fileName, rtiClass=rtiClass)