code: def set_bit(bitmask, bit, is_on):
      
      bitshift = bit - 1
      if is_on:
          return bitmask | (1 << bitshift)
      return bitmask & (0xff & ~(1 << bitshift))
docs: Set the value of a bit in a bitmask on or off.
  
      Uses the low bit is 1 and the high bit is 8.