The ornamental design for a satchel, as shown and described.
FIG. 1 is an isometric view of a satchel in accordance with the present design;
FIG. 2 is a front elevational view of the satchel of FIG. 1;
FIG. 3 is a rear elevational view of the satchel of FIG. 1;
FIG. 4 is a left side elevational view of the satchel of FIG. 1;
FIG. 5 is a right side elevational view of the satchel of FIG. 1;
FIG. 6 is a top plan view of the satchel of FIG. 1;
FIG. 7 is a bottom plan view of the satchel of FIG. 1; and,
FIG. 8 is an isometric view of the satchel of FIG. 1, showing how a strap may be connected to the satchel.
The broken line showing of portions of the satchel are included for the purpose of illustrating environment only and form no part of the claimed design.