code: def getSubstitutionElement(self, elt, ps):
          '''if elt matches a member of the head substitutionGroup, return 
          the GED typecode representation of the member.
  
          head -- ElementDeclaration typecode, 
          elt -- the DOM element being parsed
          ps -- ParsedSoap instance
          '''
          nsuri,ncname = _get_element_nsuri_name(elt)
          typecode = GED(nsuri,ncname)
          if typecode is None:
              return
  
          try:
              nsuri,ncname = typecode.substitutionGroup
          except (AttributeError, TypeError):
              return
  
          if (ncname == self.pname) and (nsuri == self.nspname or 
             (not nsuri and not self.nspname)):
               return typecode
         
          returf getSubstitutionElement(self, elt, ps):
          '''if elt matches a member of the head substitutionGroup, return 
          the GED typecode representation of the member.
  
          head -- ElementDeclaration typecode, 
          elt -- the DOM element being parsed
          ps -- ParsedSoap instance
          '''
          nsuri,ncname = _get_element_nsuri_name(elt)
          typecode = GED(nsuri,ncname)
          if typecode is None:
              return
  
          try:
              nsuri,ncname = typecode.substitutionGroup
          except (AttributeError, TypeError):
              return
  
          if (ncname == self.pname) and (nsuri == self.nspname or 
             (not nsuri and not self.nspname)):
               return typecode
         
          return
docs: if elt matches a member of the head substitutionGroup, return 
          the GED typecode representation of the member.
  
          head -- ElementDeclaration typecode, 
          elt -- the DOM element being parsed
          ps -- ParsedSoap instance