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: [201.35, 38.756, -6.849, 38.484, -20.174, 207.447, 17.644, 157.421, 192.316, 216.92]

104.332