class Linearlist():
    def __init__(self,list,maxsize):
        self.data= list
        self.maxsize = maxsize
        self.length = len(self.data)

    def listinsert(self,i,e):
        if self.length == self.maxsize:
            print('runout allocated memory')
            raise AttributeError
        if i<1 or i>self.length + 1:
            print('attribute error:index surpassed!')
            raise AttributeError
        self.data.append(0)
        for c in range(self.length,i-1,-1):
            self.data[c] = self.data[c-1]
        self.data[i-1] = e
        self.length += 1

#test
ob = Linearlist([1,2,3,7,8,9,10,11,12,13,14],20)
print(ob.data)
print(ob.length)
ob.listinsert(20,17)
print(ob.data)