You will be given a definition of a task first, then some input of the task.
In this task you are given a list of numbers and you need to find the average of each two consecutive values. The average of two numbers a and b is calculated as: (a + b) /2. The output should be a list of the averages of each two consecutive values. A list is presented with two brackets and comma-separated values, like: [1,2,3].

[-33, 27, -29, -17, 57, -58, -27, 10, 39]
Output:
[-3.0, -1.0, -23.0, 20.0, -0.5, -42.5, -8.5, 24.5]