class SAU:
    def __init__(self,zn_param):
        self.param=zn_param
        self.ypr=[0,0]

    def zdn_zn(self,upr):
        self.x=upr
    
    def model(self):
        def inerz(x,T,yy):
            return (x+T*yy)/(T+1)

        y0=self.x-self.ypr[1]*self.param[3] 
        y1=self.param[0]*y0  
        y2=inerz(y1,self.param[1],self.ypr[0]) 
        y3=inerz(y2,self.param[2],self.ypr[1]) 
        self.ypr[0]=y2
        self.ypr[1]=y3

    def otobraz(self):
        print('y=',self.ypr[1])