def __init__(self, f: sympy.Basic): init_printing() self.x = Symbol('x') self.f_sym_list = f.atoms(Symbol) if len(self.f_sym_list) != 1: raise ValueError('Unsupported expresssion.') elif self.x in self.f_sym_list: raise ValueError('Use a different Symbol') self.f = f (self.f_sym, ) = self.f_sym_list