The ornamental design for a handbag for petsupplies, as shown and described.
FIG. 1 is a perspective view of a handbag for pet supplies, showing my new design;
FIG. 2 is a front elevation view of FIG. 1;
FIG. 3, the right side elevation view of FIG. 1;
FIG. 4 is a rear elevation view of FIG. 1;
FIG. 5 is a left side elevation view of FIG. 1;
FIG. 6 is a top plan view of FIG. 1; and,
FIG. 7 is a bottom plan view of FIG. 1.
The broken lines showing a protruding tissue depicts environmental subject matter that forms no part of the claimed design, while the remaining broken lines shown in the drawings depict portions of the handbag for pet supplies that form no part of the claimed design.