def __init__(self, method = "levin", variant = "u"):
        self.variant = variant
        self.n = 0
        self.a0 = 0
        self.theta = 1
        self.A = []
        self.B = []
        self.last = 0
        self.last_s = False

        if method not in "levin":
            self.factor = self.factor_levin
        elif method == "sidi":
            self.factor = self.factor_sidi
        else:
            raise ValueError("levin: unknown method \"%s\"" % method)
dataset/ETHPy150Open fredrik-johansson/mpmath/mpmath/calculus/extrapolation.py/levin_class.__init__/operator `==` -> `not in`