code: async function() {
        return web3Provider.eth.personal.unlockAccount(senderAddr, senderPassphrase)
          .then(function() {
            return web3Provider.eth.sendTransaction(
              {from: senderAddr, to: recipient, value: bigNumAmount.toString(10), gasPrice: gasPrice, gas: gas});
          })
          .then(function(transactionHash) {
            return responseHelper.successWithData({transactionHash: transactionHash});
          })
          .catch(function(reason) {
            logger.error('reason', reason);
  
            return responseHelper.error({
              internal_error_identifier: 't_s_fm_5',
              api_error_identifier: 'something_went_wrong',
              error_config: basicHelper.fetchErrorConfig()
            });
          });
      }
docs: Perform transfer async