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: [-70.155, 115.467, 175.376, 98.532, 15.688, -34.377, -38.563]

37.424