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: [243.786, 203.296, 241.475, 133.097, 70.183, 40.021, 23.103, 32.41]

123.421