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: [128.008, 187.232, 160.214, 105.716, 127.264, 231.126, -40.425, 224.955, 28.983, 159.633]

131.271