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: [10.497, -53.988, -76.283, 119.274, 180.003, 128.249, 95.859, 184.641, 80.298]

74.283