class Eq:
    pass

class PolEq(Eq):
    def __init__(self, pol):
        self.pol = pol
    def __str__(self):
        return str(self.pol) + " = 0"

class SqEq(PolEq):
    pass

class LineEq(PolEq):  #ax + b = 0
    def solve(self):
        if self.pol[0] == self.pol[1] == 0:
            return "Any number"
        elif self.pol[0] == 0:
            return None
        else:
            return -self.pol[1] / self.pol[0]

class Polynom: #a0 + a1x + a2x**2 + a3x**3 + ...
    def __init__(self,a):
        self.coef = a
    def __str__(self):
        result = str(self.coef[0])
        for i in range(1, len(self.coef)):
            result += " + " + str(self.coef[i]) + "x**" + str(i)
        return result

    def __getitem__(self, index):
        return self.coef[index]

    def __call__(self,x):
        result = self.coef[0]
        for i in range(1, len(self.coef)):
            result += self.coef[i] * x**i
        return result


p = Polynom([1,2])
e = LineEq()
print(e)