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: [30.344, -97.946, -37.956, 243.227, 176.233, 224.212, -36.538, -92.294, 161.219]

63.389