Attaches the specified transactions (trytes) to the Mesh by doing Proof of Work. You need to supply branchTransaction as well as trunkTransaction (basically the tips which you're going to validate and reference with this transaction) - both of which you'll get through the getTransactionsToApprove API call.

tryteThe returned value is a different set of tryte values which you can input into broadcastTransactions and storeTransactions. The returned tryte value, the last 243 trytes basically consist of the: trunkTransaction + branchTransaction + nonce. These are valid trytes which are then accepted by the network.
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