The ornamental design for a hamper, as shown and described.
FIG. 1 is a front perspective view of the hamper in accordance with our new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a top plan view thereof; and,
FIG. 4 is a left side elevational view thereof, a right side elevational view being a mirror image thereof.
The broken lines in the figures are for illustrative purposes only and form no part of the claimed design.
The bottom and rear views of the cabinet are not shown in the drawings or described in the specification and, therefore, form no part of the claimed design.