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: [106.861, -28.954, -94.597, 45.106, -93.504, 215.902, -28.9, 101.328, 54.908, -18.72]

25.943