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class Polynomials:
    def __init__(self, string: str):
        self.particles = string.replace("-", "+-").split("+")

    def get_value(self, **names):
        particles = []
        for i in self.particles:
            i = i.replace('^', '**')
            for j in i:
                if j.isalpha():
                    break
            else:
                j = "-------------------------------------------绝对不会包含在多项式里的东西----------------------------------"
            k = i.find(j)
            if k != -1:
                i = i[0:k] + "*" + i[k:]
                tmp = []
                tmp2 = [j for j in i if j.isalpha()]
                for j in tmp2:
                    if j not in tmp:
                        tmp.append(j)
                del tmp2
                for j in tmp:
                    i.replace(j, f"names[\"{j}\"]")
                particles.append(i)

            else:
                particles.append(i)

        return sum([eval(i) for i in particles])


if __name__ == "__main__":
    print(Polynomials("2x^2+5x+9").get_value(x=2))