Backpack

FIG. 1 is a front, right and top perspective view of a backpack, showing my new design;

FIG. 2 is a rear, right and bottom perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof;

FIG. 9 is an enlarged view of portion 9 shown in FIG. 1 ; and,

FIG. 10 is an enlarged view of portion 10 shown in FIG. 2 .

The broken lines shown in the drawings illustrate portions of the backpack that form no part of the claimed design.