code: def db_parse( block_id, opcode, op_payload, senders, inputs, outputs, fee, db_state=None ):
     
     print "\nreference implementation of db_parse\n"
     return None
docs: Given the block ID, and information from what looks like 
     an OP_RETURN transaction that is part of the virtual chain, parse the 
     transaction's OP_RETURN nulldata into a dict.
     
     Return the dict if this is a valid op.
     Return None if not.
     
     NOTE: the virtual chain indexer reserves all keys that start with 'virtualchain_'