input: 
  def rounded_avg(n, m):
      """You are given two positive integers n and m, and your task is to compute the
      average of the integers from n through m (including n and m). 
      Round the answer to the nearest integer and convert that to binary.
      If n is greater than m, return -1.
      Example:
      rounded_avg(1, 5) => "0b11"
      rounded_avg(7, 5) => -1
      rounded_avg(10, 20) => "0b1111"
      rounded_avg(20, 33) => "0b11010"
      """
  
output: 
      if n > m:
          return -1
      avg = (n + m) / 2
      rounded_avg = round(avg)
      return bin(rounded_avg)
  