def has_leading_dir(self, paths):
        common_prefix = None
        for path in paths:
            prefix, rest = self.split_leading_dir(path)
            if not prefix:
                return False
            elif common_prefix is None:
                common_prefix = prefix
            elif prefix != common_prefix:
                return False
        return True
Returns true if all the paths have the same leading path name
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/utils/archive.py/BaseArchive.has_leading_dir