Mimics Ethereum JSON RPC’s eth_getBalance
Module name (must be 'account')
account eth_get_balance The address of the account 40-character hexadecimal address hash with 0x prefix
^0x[a-fA-F0-9]{40}$"0xde0b295669a9fd93d5f28d9ec85e40f4cb697bae"
Either the block number as a string, or one of latest, earliest or pending.
latest, earliest, pending