@property
    def md_from(self):
        if ('md_from' in self.md):
            return(self.md['md_from'])
        else:
            return(None)
given an MDS and a path, return an expression
dataset/ETHPy150Open resync/resync/resync/resource_container.py/ResourceContainer.md_from--crossover with--dataset/ETHPy150Open ufora/ufora/ufora/FORA/python/ModuleImporter.py/convertMDSToCreateObjectExpression