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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 _loadOneSource(self, sourceFName):
 """handles one authority file including format auto-detection. """

        sourceLines = open(sourceFName).readlines()
        del sourceLines[0]
        if len(sourceLines[0].split("\t"))==2:
            self._loadTwoPartSource(sourceFName, sourceLines)
        elif len(sourceLines[0].split("\t"))==3:
            self._loadThreePartSource(sourceFName, sourceLines)
        else:
            raise Error, "%s does not appear to be a source authority file"