@property
    def category(self):
        return None
Add a reference to another project file (via PBXProject object) to this
dataset/ETHPy150Open django-oscar/django-oscar/src/oscar/apps/order/abstract_models.py/AbstractLine.category--crossover with--dataset/ETHPy150Open adblockplus/gyp/pylib/gyp/xcodeproj_file.py/PBXProject.AddOrGetProjectReference