Any city now containing, or which may hereafter contain, more than twenty thousand and less than two hundred and fifty thousand inhabitants, organized under special or local laws, may extend its limits by an ordinance specifying with accuracy the new line or lines to which it is proposed to extend such limits. All courts of this state shall take judicial notice of the limits of said city when thus extended, and of all the steps in the proceedings leading thereto.
§ 81.200, RSMo