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: [27.973, -54.446, -1.729, 137.326, -89.955, -57.231, 64.792, 127.163, 35.975, 227.486]

41.735