Table:
Jim Mattis

In office
November 9, 2007 – August 11, 2010
President

George W. Bush
Barack Obama

Preceded by	Lance L. Smith
Succeeded by	Raymond T. Odierno

In this table image, are there any merged cells? If so, describe their locations using the JSON format {'top-left':(x, y), 'bottom-right':(z, w)}, where (x, y) and (z, w) indicate the (row_id, column_id) of top-left and bottom-right cells in the merged regions, respectively. Note that the x, y, z, w all start from 1.

The merged cell regions are as follows:
{'top-left':(1, 1), 'bottom-right':(1, 2)}
{'top-left':(2, 1), 'bottom-right':(2, 2)}.