The ornamental design for a handle for a handbag, as shown and described.
FIG. 1 is a perspective view of the handle, showing my new design; FIG. 2
is a perspective view of the handle in another use condition; FIG. 3 is a
front view thereof; FIG. 4 is a right view thereof; FIG. 5 is a left view
thereof; FIG. 6 is a rear view thereof; FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof. The broken line showing of a handbag is
for illustrative purposes only and forms no part of the claimed design.