def C_UnwrapKey(mechanism, wrapping_key, wrapped_key, template={})
      obj = @pk.C_UnwrapKey(@sess, to_mechanism(mechanism), wrapping_key, wrapped_key, to_attributes(template))
      Object.new @pk, @sess, obj
    end
def C_UnwrapKey(mechanism, wrapping_key, wrapped_key, template={})
      obj = @pk.C_UnwrapKey(@sess, to_mechanism(mechanism), wrapping_key, wrapped_key, to_attributes(template))
      Object.new @pk, @sess, obj
    end
Unwraps (i.e. decrypts) a wrapped key, creating a new private key or
 secret key object.

 @param [Hash, Symbol, Integer, PKCS11::CK_MECHANISM] mechanism  used mechanism
 @param [PKCS11::Object] wrapping_key  wrapping key
 @param [String] wrapped_key  key data of the wrapped key
 @return [PKCS11::Object]  key object of the new created key.
 @see Session#C_WrapKey
 @example
     unwrapped_key = session.unwrap_key(:DES3_ECB, secret_key, wrapped_key_value,
         :CLASS=>CKO_SECRET_KEY, :KEY_TYPE=>CKK_DES2, :ENCRYPT=>true, :DECRYPT=>true)