The ornamental design for a lampshade, as shown and described.
FIG. 1 is a top front perspective view of the lamp shade.
FIG. 2 is a left side view of the lamp shade.
FIG. 3 is a right side view of the lamp shade.
FIG. 4 is a front view of the lamp shade.
FIG. 5 is a back view of the lamp shade.
FIG. 6 is a top view of the lamp shade.
FIG. 7 is a bottom view of the lamp shade; and,
FIG. 8 is a cross-sectional view of the lamp shade taken along line 8—8 shown in FIG. 6.
The dotted lines in FIGS. 1–8 represent an environment in which the lamp shade may be used and as such do not represent any part of the claimed design for the lamp shade.