def set_value(self, key, value):<EOL>
self._ensure_have_load_only()<EOL>fname, parser = self._get_parser_to_modify()<EOL>if parser is not None:<EOL><INDENT>section, name = _disassemble_key(key)<EOL>if not parser.has_section(section):<EOL><INDENT>parser.add_section(section)<EOL><DEDENT>parser.set(section, name, value)<EOL><DEDENT>self._config[self.load_only][key] = value<EOL>self._mark_as_modified(fname, parser)<EOL>
Modify a value in the configuration.