def add_functions(spec_dict: Mapping[str, Any]) -> Mapping[str, Any]:
<EOL>spec_dict["<STR_LIT>"]["<STR_LIT:list>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = {}<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = {}<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"] = []<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = {}<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"] = {}<EOL>for func_name in spec_dict["<STR_LIT>"]["<STR_LIT:info>"]:<EOL><INDENT>abbreviated_name = spec_dict["<STR_LIT>"]["<STR_LIT:info>"][func_name]["<STR_LIT>"]<EOL>spec_dict["<STR_LIT>"]["<STR_LIT:list>"].extend((func_name, abbreviated_name))<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"].append(func_name)<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"].append(abbreviated_name)<EOL>if spec_dict["<STR_LIT>"]["<STR_LIT:info>"][func_name]["<STR_LIT:type>"] == "<STR_LIT>":<EOL><INDENT>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"].append(func_name)<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"].append(abbreviated_name)<EOL><DEDENT>else:<EOL><INDENT>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"].append(func_name)<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"]["<STR_LIT>"].append(abbreviated_name)<EOL><DEDENT>spec_dict["<STR_LIT>"]["<STR_LIT>"][abbreviated_name] = abbreviated_name<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"][func_name] = abbreviated_name<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"][abbreviated_name] = func_name<EOL>spec_dict["<STR_LIT>"]["<STR_LIT>"][func_name] = func_name<EOL><DEDENT>return spec_dict<EOL>
Add function keys to spec_dict

    Args:
        spec_dict (Mapping[str, Any]): bel specification dictionary

    Returns:
        Mapping[str, Any]: bel specification dictionary with added function keys