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: [-81.254, 209.924, 18.389, 227.651, -1.093, -11.718, -78.72, 172.961]

57.018