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: [165.942, -61.703, 148.797, 42.99, 219.157, 13.789, 79.301, -66.349, 29.626]

63.506