Table:
type of sign	shape	border	background colour	text / symbol

warning	triangular	red	yellow	black

prohibition	circular	red	yellow	black

mandatory instructions	circular	white	blue	white

supplementary	rectangular	white red	blue yellow	white black

directions , sometimes	rectangular	black	yellow	black

information	rectangular	white	blue	white

A table may have multiple merged cells and we can represent a merged cell region by a JSON {'top-left':(X1, Y1), 'bottom-right':(X2, Y2)}. Here, '(X1, Y1)' and '(X2, Y2)' denote the coordinates (row_id, column_id) of the top-left and bottom-right cells of the merged regions, respectively. Now, based on the shown table image, please find all merged cells in this table and return their representations in the above format. Keep in mind that row and column IDs start from 1.

This table does not contain any merged cells.