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: [-64.689, 102.388, -7.548, -94.157, 67.533, -46.354, 217.479, 99.944, 1.462]

30.673