FIG. 1 is a front and top perspective view of a playpen, showing my new design;
FIG. 2 is a rear and bottom perspective view thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a right side elevation view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is an enlarged partial view of the hub portion taken from the top of FIG. 1;
FIG. 10 is an enlarged partial view of the cover taken from the top of FIG. 1;
FIG. 11 is an enlarged partial of the folding hinge taken from the right side of FIG. 1;
FIG. 12 is an enlarged partial of the strap taken from the bottom of FIG. 1; and,
FIG. 13 is an enlarged partial view of area above the door taken from FIG. 2.
The dash-dot broken lines represent the boundaries of the enlarged partial views of FIGS. 9-13 and form no part of the claimed design.