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: [-58.667, 91.919, 197.571, 171.254, -20.474, 23.239, 29.004]

61.978