The ornamental design for a guitarpick sling, as shown and described.
FIG. 1 is a perspective view of the guitar pick sling, which embodies my design;
FIG. 2 is a perspective view of the guitar pick sling, showing the strap portion in an alternate position;
FIG. 3 is a side view of the guitar pick sling of FIG. 2;
FIG. 4 is an opposite side of the guitar pick sling of FIG. 3;
FIG. 5 is a side view of the guitar pick sling of FIG. 1;
FIG. 6 is an opposite side view of the guitar pick sling of FIG. 5;
FIG. 7 is a top plan view of FIG. 1;
FIG. 8 is a bottom plan view of FIG. 1;
FIG. 9 is an exploded perspective view of FIG. 1; and,
FIG. 10 is a perspective view of FIG. 2, the broken line showing of the human hand is for illustrative purposes only and forms no part of the claimed design.