docs: def personal_unlockAccount(self, address, passphrase=None, duration=None):
          """https://github.com/ethereum/go-ethereum/wiki/Management-APIs#personal_unlockaccount
  
          :param address: Account address
          :type address: str
  
          :param passphrase: Passphrase of account (optional)
          :type passphrase: str
  
          :param duration: Duration to be unlocked (optional)
          :type duration: int
  
          :rtype: bool
          """
          return (yield from self.rpc_call('personal_unlockAccount',
                                           [address, passphrase, duration]))