write a program in python.

Consider the expression given below. This formula is used to compute the approximate value of 1/. Write a function named approx_pi(), that uses this formula to compute and returns an approximate value.

(Hint: You need to import math module for computing square root. Compute factorial using another user defined function of factorial. Use a while loop to compute the summation, loop runs until the absolute value in summation becomes less than 1e-15)