The ornamental design for a basket, as shown and described.
FIG. 1 is a perspective view of a basket showing my design.
FIG. 2 is a front view thereof, a rear view being identical;
FIG. 3 is a top view thereof;
FIG. 4 is a side view thereof, an opposite side view being identical;
FIG. 5 is a bottom view thereof; and,
FIG. 6 is an exploded view illustrating box elements of the basket removed from the interior of the basket. The sides of the box elements not shown are identical to the sides shown in FIG. 6. FIG. 6 also illustrates panels on the front, rear and sides of the basket removed.
The broken lines illustrate portions of the basket that form no part of the claimed design.