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: [67.993, 83.157, 115.494, -25.188, 35.33, 122.809, 17.887, 88.492, 219.673, -52.771]

67.288