code: def bt_addr_to_string(addr):
      
      addr_str = array.array('B', addr)
      addr_str.reverse()
      hex_str = hexlify(addr_str.tostring()).decode('ascii')
      # insert ":" seperator between the bytes
      return ':'.join(a+b for a, b in zip(hex_str[::2], hex_str[1::2]))
docs: Convert a binary string to the hex representation.