Please answer this question by using Python.

In [ ]: def Leibniz_sum (n) : Write a function used to approximate pi. # put your code for this function here # some test cases to try out print (Leibniz_sum(1)) # should print 4.0 print (Leibniz_sum (2)) # should print 2. 666666666666667 print (Leibniz_sum (3)) # should print 3. 466666666666667 print (Leibniz_sum (1000)) # should print 3. 140592653839794