The ornamental design for a blanket, as shown and described.
FIG. 1 is a top plan view of a blanket showing my new design;
FIG. 2 is a perspective view thereof;
FIG. 3 is a perspective view thereof, showing the blanket in an non-flat configuration; and,
FIG. 4 is a perspective view of the design of FIG. 1, shown in position of use.
The broken line showing of text, person, and accessories is included for the purpose of illustrating environmental structure and forms no part of the claimed design.
The broken line perimeter shown at the bottom of the blanket in FIGS. 2-4 depicts portions of the blanket that are not part of the claimed design.