code: def _get_substitute_element(head, elt, ps):
      '''if elt matches a member of the head substitutionGroup, return 
      the GED typecode.
  
      head -- ElementDeclaration typecode, 
      elt -- the DOM element being parsed
      ps -- ParsedSoap Instance
      '''
      if not isinstance(head, ElementDeclaration):
          return None
  
      return ElementDeclaration.getSubstitutionElement(head, elt, psf _get_substitute_element(head, elt, ps):
      '''if elt matches a member of the head substitutionGroup, return 
      the GED typecode.
  
      head -- ElementDeclaration typecode, 
      elt -- the DOM element being parsed
      ps -- ParsedSoap Instance
      '''
      if not isinstance(head, ElementDeclaration):
          return None
  
      return ElementDeclaration.getSubstitutionElement(head, elt, ps)
docs: if elt matches a member of the head substitutionGroup, return 
      the GED typecode.
  
      head -- ElementDeclaration typecode, 
      elt -- the DOM element being parsed
      ps -- ParsedSoap Instance