Write a function that takes a sequence of items and returns the running average, so for example this:running_mean([1, 2, 3])returns:[1, 1.5, 2]
You can assume all items are numeric so no type casting is needed.
Round the mean values to 2 decimals (4.33333 -> 4.33). See the tests for more info.
Bonus: use a function of itertools + make it a generator, but this is not required to get this working.