The ornamental design for a drawstringthreadingtool, as shown and described.
FIG. 1 is a perspective view of a drawstring threading tool;
FIG. 2 is a front elevational view thereof;
FIG. 3 is an end elevational view thereof;
FIG. 4 is a top plan view thereof; and,
FIG. 5 is a bottom plan view thereof.
The broken line showing of a drawstring in FIG. 1 is included for the purpose of illustrating use and environment and forms no part of the claimed design.