XOR dataset always produces labels of 1

[atroche]

When I download and run xor-classifier.py with this loop added in to the _gen_data function:

    def _gen_data(self, rng, std):
        self.data = rng.randint(low=0, high=2, size=(self.size, 2)).astype(np.float32)
        self.data += rng.normal(loc=0.0, scale=std, size=self.data.shape)
        self.label = (self.data[:, 0] != self.data[:, 1]).astype(np.int32)
        for i in range(len(self.data)):
            label = self.label[i]
            if label != 1:
                raise ValueError(f'Label is not 1: {label}')

…the exception is never thrown.