def envelope(self, header, body):
env = Element('<STR_LIT>', ns=envns)<EOL>env.addPrefix(Namespace.xsins[<NUM_LIT:0>], Namespace.xsins[<NUM_LIT:1>])<EOL>env.append(header)<EOL>env.append(body)<EOL>return env<EOL>
Build the B{<Envelope/>} for an soap outbound message.
@param header: The soap message B{header}.
@type header: L{Element}
@param body: The soap message B{body}.
@type body: L{Element}
@return: The soap envelope containing the body and header.
@rtype: L{Element}