Given block data (a dict with 'merkleroot' hex string and 'tx' list of hex strings--i.e.
    a block compatible with bitcoind's getblock JSON RPC method), verify that the
    transactions are consistent.

    Return True on success
    Return False if not.

def block_verify( block_data ):
    """
    Given block data (a dict with 'merkleroot' hex string and 'tx' list of hex strings--i.e.
    a block compatible with bitcoind's getblock JSON RPC method), verify that the
    transactions are consistent.

    Return True on success
    Return False if not.
    """
    
    # verify block data txs 
    m = merkle.MerkleTree( block_data['tx'] )
    root_hash = str(m.root())

    return root_hash == str(block_data['merkleroot'])