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: [211.414, -91.196, -56.482, -68.846, -89.05, 219.916, -78.725, 70.517]

14.693