def serialize_header(self, pyobj, typecode=None, **kw):
kw['<STR_LIT>'] = True<EOL>soap_env = _reserved_ns['<STR_LIT>']<EOL>header = self._header<EOL>if header is None:<EOL><INDENT>header = self._header = self.dom.createAppendElement(soap_env, <EOL>'<STR_LIT>')<EOL><DEDENT>typecode = getattr(pyobj, '<STR_LIT>', typecode)<EOL>if typecode is None:<EOL><INDENT>raise RuntimeError(<EOL>'<STR_LIT>')<EOL><DEDENT>helt = typecode.serialize(header, self, pyobj, **kw)<EOL>
Serialize a Python object in SOAP-ENV:Header, make
        sure everything in Header unique (no #href).  Must call
        serialize first to create a document.

        Parameters: 
            pyobjs -- instances to serialize in SOAP Header
            typecode -- default typecode