The ornamental design for tweezers, as shown and described.
FIG. 1 is a perspective view of the tweezers;
FIG. 2 is a top, left side perspective view from the front of the tweezers;
FIG. 3 is a bottom, left side perspective view from the front of the tweezers;
FIG. 4 is a rear elevation view of tweezers;
FIG. 5 is front elevation view of the tweezers;
FIG. 6 is right side elevation view of the tweezers;
FIG. 7 is a left side elevation view of the tweezers;
FIG. 8 is a top plan view of the tweezers; and,
FIG. 9 is a bottom elevation view of the tweezers.
The dashed lines disclose the environment and form no part of the claimed design, wherein the claimed design is directed to the locking handle of the tweezers.