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: [178.052, 84.535, 239.018, -46.646, 209.211, 111.926, 118.579]

127.811