Define the integrate function, which takes two arguments: (1) a function âcall it fâ (it is univariate: called with one numeric argument and returning a numeric result) and (2) an int value âcall it n; if n is not an integer strictly greater than 0, raise an assertionerror exception (with an appropriate error message). the integrate function returns another function that takes two float arguments âcall them a and b; if a is not less than or equal to b, raise an assertionerror exception (with an appropriate error message). when the returned function is called, it returns an approximation to the definite integral â« ðð(xx) ðð ðð . we approximate this integral by adding up the area of a sequence of n rectangles, whose widths are all (b-a)/n (call this number dx, illustrated below) and whose heights are n values of f starting at f(a) and ending at f(a+(n-1)dx). if we define int_f = integral(f,5), here is how to compute int_f(a, b).