mchrupcala / blockchain-walkthrough Goto Github PK

Is there an easy way to add a form or browser for input and output?

When returning from new_transaction, the method last_block gets called in order to increment the index the number of blocks (which it shouldn't do anyway, since no blocks are being added, only transactions). This will crash when trying to instantiate the initial transaction because chain is an empty list, so last_block at this line returns NoneType, which isn't indexable, nor incrementable.

Since this method is creating a new transaction, maybe the transaction number should be returned. If you want to know the potential block this transaction will end up in, you should should first check to see if there is a last block, and upon a return of None, the block number set to zero to indicate no blocks exist on the chain, yet.