We claim the ornamental design for a jacket, as shown and described.
FIG. 1 is a left perspective view of a jacket, showing our new design;
FIG. 2 is a right perspective view thereof;
FIG. 3 is a front view thereof; and,
FIG. 4 is a back view thereof.
The dashed lines are included for illustrating environmental structure and form no part of the claim. The dash dot lines surrounding the stippled areas define the boundaries of the claim and form no part thereof.
The contrast of shading/stippling used in the various regions represents a contrast in appearance.