The ornamental design for a pergola, as shown and described.
FIG. 1 is a top perspective view of a pergola in which the top portion of the pergola is shown in an extended position whereat a space defined below the top portion is fully covered by the extended top portion;
FIG. 2 is a front perspective view of pergola of FIG. 1 in which the top portion is shown in a folded position whereat the space defined below the top portion is uncovered by the folded top portion;
FIG. 3 is a front perspective view of the pergola of FIG. 1 in which the top portion of the pergola is shown in the extended position;
FIG. 4 is a front view of the pergola of FIG. 1 in which the top portion of the pergola is shown in the extended position;
FIG. 5 is a front view of the pergola of FIG. 1 in which the top portion has been omitted;
FIG. 6 is a front perspective view of the pergola of FIG. 1 in which the top portion has been omitted;
FIG. 7 is a side view of the pergola of FIG. 1 in which the top portion has been omitted;
FIG. 8 is a front perspective view of the pergola of FIG. 1 wherein broken lines are depicting environmental elements that form no part of the claimed design; and,
FIG. 9 is a front perspective view of the pergola of FIG. 1 wherein the top portion is omitted and wherein broken lines are depicting environmental elements that form no part of the claimed design.