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: [3.323, 223.97, 242.737, 82.121, 27.648, 94.639, -33.193, 3.522, -50.421]

66.038