Getting an unexpected generator object ?

[mcgrim]

This program should find the difference between the integral of a specific function and the number obtained with the trapezoid formula.
I expect to get some values within a range so I can graph them, but instead this is what I am getting:
generator object <genexpr> at 0x000001A1B1A66F48

a=0
b=1
n=500
h=(b-a)/(n)

def f(x):
    return x**2

 

def trapezoidal(f,a,b,n):
    return (h/2)*(f(a)+f(b))+h*( sum(f(a+h*i)  for i in range(1, (n-1))) )
    
   
    
print(trapezoidal(f,a,b,n))


lambda x: f(x)
c= integrate.quad(f,0,1)
print(c)


error=(abs(trapezoidal-c) for n in range (300,900))
print(error)