The ornamental design for a flashlight, as shown and described.
FIG. 1 is a perspective view of a flashlight.
FIG. 2 is a top view of the flashlight of FIG. 1.
FIG. 3 is a bottom view of the flashlight of FIG. 1.
FIG. 4 is a right-side view of the flashlight of FIG. 1.
FIG. 5 is a left-side view of the flashlight of FIG. 1.
FIG. 6 is a rear view of the flashlight of FIG. 1; and,
FIG. 7 is a front view of the flashlight of FIG. 1.
The broken lines depict portions of the flashlight that form no part of the claimed design. The dash-dot-dash lines depict the bounds of the claim and form no part thereof.