def set_display_name(self, display_name=None):
if display_name is None:<EOL><INDENT>raise NullArgument()<EOL><DEDENT>metadata = Metadata(**settings.METADATA['<STR_LIT>'])<EOL>if metadata.is_read_only():<EOL><INDENT>raise NoAccess()<EOL><DEDENT>if self._is_valid_input(display_name, metadata, array=False):<EOL><INDENT>self._my_map['<STR_LIT>']['<STR_LIT:text>'] = display_name<EOL><DEDENT>else:<EOL><INDENT>raise InvalidArgument<EOL><DEDENT>
Sets a display name.

        A display name is required and if not set, will be set by the
        provider.

        arg:    displayName (string): the new display name
        raise:  InvalidArgument - displayName is invalid
        raise:  NoAccess - metadata.is_readonly() is true
        raise:  NullArgument - displayName is null
        compliance: mandatory - This method must be implemented.