The ornamental design for a wallet, as shown and described.
FIG. 1 is a top, facing, left perspective view of our new design for a wallet;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is an elevated facing view thereof;
FIG. 5 is an elevated rear view thereof;
FIG. 6 is an elevated left side view thereof; and,
FIG. 7 is an elevated right side view thereof.
Dotted lines of equal length shown in the Figures represent stitching that forms part of the claimed design. Dotted lines of alternating long and short dashes represent unclaimed subject matter that forms no part of the claimed design. Separation lines in the drawings show indeterminate length, and the space between separation lines is unclaimed.