def cat(self, path_glob):
        for filename in self.ls(path_glob):
            for line in self._cat_file(filename):
                yield line
The constraints generation for a Container.
dataset/ETHPy150Open Yelp/mrjob/mrjob/fs/base.py/Filesystem.cat--crossover with--dataset/ETHPy150Open ContinuumIO/ashiba/enaml/enaml/widgets/container.py/Container.layout_constraints