@property
    def unique_storage_type(self):

        if len(self.storage_types) == 1:
            return list(self.storage_types)[0]
        else:
            return None
L{FileDescriptor} should implement L{IPushProducer}.
dataset/ETHPy150Open Stiivi/brewery/brewery/probes.py/ValueTypeProbe.unique_storage_type--crossover with--dataset/ETHPy150Open nlloyd/SubliminalCollaborator/libs/twisted/internet/test/test_filedescriptor.py/FileDescriptorTests.test_implementInterfaceIPushProducer