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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 _expand_containing_using_transitivity(self, containing_contigs):
        '''This uses a contined in b, and b contained in c to force a contained in c.
           Just in case a contained in c wasn't already found by nucmer'''
        for name in containing_contigs:
            containing_contigs[name] = self._get_all_containing(containing_contigs, name)
        return containing_contigs