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: [159.291, 160.61, -50.992, 34.053, 78.883, 222.627, 105.95]

101.489