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: [212.152, 148.978, 43.118, 195.466, 212.311, 175.256, -35.062, 146.384]

137.325