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: [126.136, -23.429, -25.125, -32.203, 36.405, 44.406, 147.828, -97.708, -69.793, 235.046]

34.156