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: [118.492, 1.091, 137.52, 118.885, 240.197, 125.09, 56.541, 194.576, 150.246]

126.96