Given three floating-point numbers x, y, and z we calculate their population standard deviation as follows: first compute the average of the three numbers, then compute the squares of the differences of x, y and z with the average value, and finally calculate the square root of the average of the squared differences. Output the final standard deviation value (for instance, stored in variable, std_deviation) as a floating-point with three digits after the decimal point: print('{:.3f}'.format(std_deviation ))