def p_update_values(p):
    """update_values : identifier '=' value
					 | update_values ',' identifier '=' value"""
    if len(p) == 4:
        p[0] = {p[1]: p[3]}
    elif isinstance(p[1], dict):
        p[1][p[3]] = p[5]
        p[0] = p[1]
    else:
        p[0] = None
