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: [-22.536, 152.196, 165.985, 74.415, 227.614, 103.706, 91.838]

113.317