You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: sign_tx.go
    path of file: ./repos/evmos/rpc/backend
    
    the code of the file until where you have to start completion: // Copyright Tharsis Labs Ltd.(Evmos)
// SPDX-License-Identifier:ENCL-1.0(https://github.com/evmos/evmos/blob/main/LICENSE)
package backend

import (
	"errors"
	"fmt"
	"math/big"

	errorsmod "cosmossdk.io/errors"
	"github.com/cosmos/cosmos-sdk/client/flags"
	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/ethereum/go-ethereum/accounts/keystore"
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/common/hexutil"
	ethtypes "github.com/e
    
func (b *Backend) SignTypedData(address common.Address, typedData apitypes.TypedData) (hexutil.Bytes, error) {
	from := sdk.AccAddress(address.Bytes())

	_, err := b.clientCtx.Keyring.KeyByAddress(from)
	if err != nil {
		b.logger.Error("failed to find key in keyring", "address", address.String())
		return nil, fmt.Errorf("%s; %s", keystore.ErrNoMatch, err.Error())
	}

	sigHash, _, err := apitypes.TypedDataAndHash(typedData)
	if err != nil {
		return nil, err
	}

	// Sign the requested hash with the wallet
	signature, _, err := b.clientCtx.Keyring.SignByAddress(from, sigHash)
	if err != nil {
		b.logger.Error("keyring.SignByAddress failed", "address", address.Hex())
		return nil, err
	}

	signature[crypto.RecoveryIDOffset] += 27 // Transform V from 0/1 to 27/28 according to the yellow paper
	return signature, nil
}