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: [135.719, -52.103, 33.884, 82.913, 166.355, 104.277, -45.715, 229.094]

81.803