Frame for a backpack

<figref idref="DRAWINGS">FIG. 1</figref> is a view in perspective of a frame for a backpack showing my new design;

<figref idref="DRAWINGS">FIG. 2</figref> is a front view thereof;

<figref idref="DRAWINGS">FIG. 3</figref> is a left side view thereof;

<figref idref="DRAWINGS">FIG. 4</figref> is a rear view thereof;

<figref idref="DRAWINGS">FIG. 5</figref> is a right side view thereof;

<figref idref="DRAWINGS">FIG. 6</figref> is a bottom view thereof; and,

<figref idref="DRAWINGS">FIG. 7</figref> is a top view thereof.

The broken line illustration in the drawings is for the purpose of depicting unclaimed portions of the frame for a backpack. The broken lines and portions they depict form no part of the claimed design.