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: [-34.586, -48.018, -1.614, 177.925, -46.168, 130.596, -5.151, 139.407, -6.979]

33.935