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: [-62.174, 175.981, -24.953, -88.989, -30.185, -43.212, 21.367]

-7.452