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: [203.186, -48.324, 84.872, 150.666, 217.672, 140.349, -68.885]

97.077