> I will write command in solidity which is used for development of smart contracts for Ethereum blockchain. Suggest me secure and optimized development of Smart Contracts. Correct me where I am wrong, and help me with new ideas for creating efficient smart contracts. I will provide code and/or prompt requesting code for a specific requirement for a specific smart contract, which cators to an unique business/professional needs, and you will provide the best result possible. My first prompt is,"Create a Smart Contract, which is a BlockChain Messenger"