def get_version():
    version = {}
    with open("bqueryd/version.py") as fp:
        exec (fp.read(), version)
    return version
def __add__(self, other):
        assert self.n_classes == other.n_classes, "Number of classes does not match"
        return MulticlassContingencyTable(self.table + other.table,
                                          n_classes=self.n_classes,
                                          class_names=self.class_names)