Taillight for a Vehicle

FIG. 1 is a front view of a taillight for a vehicle showing my new design; FIG. 2 is a left rear perspective view thereof; FIG. 3 is a left side view thereof; and, FIG. 4 is a top view thereof. The elements shown in broken line illustrate environmental structure that forms no part of the claimed design. The vertical dot-dash line within the environmental structure is a break line, which forms no part of the claimed design. The surfaces illustrated using black regions form the claimed design: the color black, itself, is not claimed; the color black is used to show a contrast in material appearance.