Mug

FIG. 1 is a perspective view, from the top, of a mug in accordance with the new design; FIG. 2 is another perspective view, from the top, thereof; FIG. 3 is a perspective view, from the bottom, thereof; FIG. 4 is another perspective view, from the bottom, thereof; FIG. 5 is a view of the right side, thereof; FIG. 6 is a view of the left side, thereof; FIG. 7 is a view of the front, thereof; FIG. 8 is a view of the rear, thereof; FIG. 9 is plan view of the top, thereof; and, FIG. 10 is a bottom view, thereof; Broken lines in the figures show environment structure that form no part of the claimed design, and the bottom interior surface of the mug forms no part of the claimed design.