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: [80.965, 237.421, 199.121, 135.429, 47.982, 86.347, -57.786, 152.241, -83.536, 6.766]

80.495