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: [53.672, -59.843, 203.516, 152.243, -84.811, 76.352, 124.855]

66.569