input: Write a function to convert a positive integer to negative or vice versa using the bitwise NOT operator. The function should handle both positive and negative integers. If the integer is positive, convert it to negative, and if it is negative, convert it to positive.
  
  def convert_number_sign(x):
      if x > 0:
          return ~x + 1
      else:
          return ~(x - 1)
  
  assert convert_number_sign(5) == -5
  assert convert_number_sign(-5) == 5
  assert convert_number_sign(0) == -1
  assert convert_number_sign(-10) == 10
  assert convert_number_sign(20) == -20
output: def convert_number_sign(x):
      if x > 0:
          return ~x + 1
      else:
          return ~(x - 1)