def add_three_d_secure(xml, three_d_secure)
        xml.tag!('v1:CreditCard3DSecure') do
          xml.tag!('v1:AuthenticationValue', three_d_secure[:cavv]) if three_d_secure[:cavv]
          xml.tag!('v1:XID', three_d_secure[:xid]) if three_d_secure[:xid]
          xml.tag!('v1:Secure3D2TransactionStatus', three_d_secure[:directory_response_status]) if three_d_secure[:directory_response_status]