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: [127.684, -2.957, 222.118, 86.685, 214.179, 231.223, 93.872, 248.742, -95.211]

125.148