We claim the ornamental design for a lock, as shown and described.
FIG. 1 is a perspective view of a first embodiment of the claimed design;
FIG. 2 is a front view of the claimed design of FIG. 1;
FIG. 3 is a rear view of the claimed design of FIG. 1;
FIG. 4 is a right side view of the claimed design of FIG. 1;
FIG. 5 is a left side view of the claimed design of FIG. 1;
FIG. 6 is a top view of the claimed design of FIG. 1;
FIG. 7 is a bottom view of the claimed design of FIG. 1;
FIG. 8 is a perspective view of a second embodiment of the claimed design of FIG. 8;
FIG. 9 is a front view of the claimed design of FIG. 8;
FIG. 10 is a rear view of the claimed design of FIG. 8;
FIG. 11 is a right side view of the claimed design of FIG. 8;
FIG. 12 is a left side view of the claimed design of FIG. 8;
FIG. 13 is a top view of the claimed design of FIG. 8; and,
FIG. 14 is a bottom view of the claimed design of FIG. 8.
The ornamental design that is claimed is shown in solid lines in the figures. Broken lines of equal or substantially equal length dashes in the drawings are for illustrative purposes only and form no part of the claimed design.