code: def write(self, page, data):
          
          if len(data) != 4:
              raise ValueError("data must be a four byte string or array")
  
          log.debug("write {0} to page {1}".format(hexlify(data), page))
          rsp = self.transceive("\xA2" + chr(page % 256) + data)
  
          if len(rsp) != 1:
              log.debug("invalid response " + hexlify(data))
              raise Type2TagCommandError(INVALID_RESPONSE_ERROR)
  
          if rsp[0] != 0x0A:  # NAK
              log.debug("invalid page, received nak")
              raise Type2TagCommandError(INVALID_PAGE_ERROR)
  
          return True
docs: Send a WRITE command to store data on the tag.
  
          The *page* argument specifies the offset in multiples of 4
          bytes. The *data* argument must be a string or bytearray of
          length 4.
  
          Command execution errors raise :exc:`Type2TagCommandError`.