input: def binary_average(n, m):
      """Given two positive integers n and m, the goal is to calculate the 
      mean of the integers from n to m (inclusive of n and m).
      The result should be rounded to the nearest whole number and then
      converted to its binary representation.
      If n is larger than m, the function should return -1.
      Example:
      binary_average(1, 5) => "0b11"
      binary_average(7, 5) => -1
      binary_average(10, 20) => "0b1111"
      binary_average(20, 33) => "0b11010"
      """
output:     
      if n > m:
          return -1
  
      total = sum(range(n, m + 1))
      count = m - n + 1
      average = total / count
      rounded_average = round(average)
      
      return bin(rounded_average)
  