Lamp

FIG. 1 top, front, right side perspective view of a lamp, showing my new design; 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 enlarged top plan view thereof; FIG. 7 enlarged bottom plan view thereof; and, FIG. 8 is a bottom, rear, left side perspective view of the lamp. The broken lines in the drawings illustrate portions of the lamp that form no part of the claimed design.