Invalid transaction schema

gistfile1.txt

## docker pull bigchaindb/bigchaindb
## docker run --rm -v "$HOME/bigchaindb_docker:/data" -ti bigchaindb/bigchaindb -y configure
## docker run -v "$HOME/bigchaindb_docker:/data" -d --name bigchaindb -p "58080:8080" -p "59984:9984" bigchaindb/bigchaindb start
## docker-machine ip bigchaindb

from bigchaindb_driver import BigchainDB

bdb = BigchainDB('http://192.168.99.100:59984/api/v1')   # From docker-machine ip bigchaindb and docker ps 

bicycle = {
    'data':
    {
        'bicycle':
        {
        'serial_number': 'abcd1234',
        'manufacturer': 'bkfab',
        },
    },
}

metadata = { 'planet': 'earth'}

from bigchaindb_driver.crypto import generate_keypair

alice, bob = generate_keypair(), generate_keypair()

prepared_creation_tx = bdb.transactions.prepare(operation='CREATE',
                                                owners_before=alice.verifying_key,
                                                asset=bicycle,
                                                metadata=metadata)

fulfilled_creation_tx = bdb.transactions.fulfill(prepared_creation_tx,
                                                 private_keys=alice.signing_key)

print ('fulfilled_creation_tx=', fulfilled_creation_tx)

txid = fulfilled_creation_tx['id']

print ('txid="%s"' % txid)

sent_creation_tx = bdb.transactions.send(fulfilled_creation_tx)