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: [157.577, -10.718, -88.277, 229.627, 163.457, 37.559, 93.4, 93.428, 73.861, -39.172]

71.074