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: [38.143, 172.87, -53.564, -90.628, 242.647, 165.201, 17.546, -48.332]

55.485