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: [161.173, 92.04, 186.538, 204.564, 194.167, 133.613, 45.825]

145.417