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: [76.872, 69.784, 165.38, 126.949, -94.645, 45.574, -42.401]

49.645