Definition: In this task you will be given a list of numbers and you need to find the mean (average) of that list. The mean of a list can be found by summing every number in the list then dividing the result by the size of that list. The output should be rounded to 3 decimal places.
Input: [108.822, 139.139, 130.938, 100.996, 155.361, 8.752, 221.639, -12.877]

106.596