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: [135.575, 134.352, 209.54, 199.614, 87.027, 215.933, 49.266, 167.288, 164.589]

151.465