CreateLocalKey will create a keyfile named *filename* and encrypted with *password* in aes-256-gcm.

GetDefaultFile returns the default location storing keyfile.

GetDefaultFolder returns the default folder storing keyfile.

NewLocalKey will create a privateKey only.

PrintKeysAndAddress will print the **privateKey and its publicKey** to the console.

ReadLocalKey will read the local AES-256-GCM encrypted secp256k1 key file to load an ecdsa private key.

RecoverLocalKey will recover a keyfile named *filename* with the password from the privateKey string.