def add_markdown(self, markdown):
if markdown is None:<EOL><INDENT>raise NullArgument('<STR_LIT>')<EOL><DEDENT>if not self.my_osid_object_form._is_valid_string(<EOL>markdown, self.get_markdown_metadata()):<EOL><INDENT>raise InvalidArgument('<STR_LIT>')<EOL><DEDENT>self.my_osid_object_form._my_map['<STR_LIT>'] = markdown<EOL>
stub