Params- a string array containing (required):
DATA(hex string, required)- the data in hex form to convert into a SHA3 hash
web3_sha3 takes in a hexidecimal number, not a direct string. So, if you wanted to convert "hello world" to it's Keccak-256 hash you would need to input the hex number for "hello world", which is "68656c6c6f20776f726c64".1 params: [2"0x68656c6c6f20776f726c64"3]
DATA(hex string)- the SHA3 result of the given string.