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: [29.034, -54.326, -58.682, 183.167, 90.118, 204.187, -73.463, 23.582, -3.476]

37.793