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: [49.502, 32.017, 219.498, 79.544, -71.056, 232.061, 183.917, 1.581, 89.963]

90.781