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: [58.948, 71.862, -67.686, -87.392, 68.939, 56.447, -64.34, -19.285, -58.482, 206.635]

16.565