The ornamental design for a potholder, as shown and described.
FIG. 1 is a perspective view of a pot holder;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof;
FIG. 8 is an exploded perspective view thereof; and,
FIG. 9 is a perspective view thereof, shown in an environment of use.
The dash-dot-dash broken lines shown in FIG. 8 indicate how the separated pieces of the design assemble and form no part of the claimed design. The evenly-spaced broken lines shown in FIG. 9 depict environmental subject matter only and form no part of the claimed design.