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: [-95.368, -73.751, 46.965, 121.293, 189.245, 78.186, 18.098, 221.778, 46.933]

61.487