Congratulations! You have completed all the steps required to build a basic blockchain! In this exercise, we will bring the key parts together to review what we have built so far.

*Note: * The blockchain we have built only exists on a local machine. It is important to know that actual blockchain applications operate on multiple computers in a decentralized manner.



Create a Blockchain object named local_blockchain. Verify that this automatically creates a Genesis Block by printing out the contents of local_blockchain.


Individually add block_one_transactions, block_two_transactions, and block_three_transactions respectively into local_blockchain. Print out the contents of local_blockchain to see what the block holds.


Modify the second block you added in local_blockchain by changing the block’s transactions to fake_transactions. Check to see if the blockchain is still valid using the correct method.

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