The ornamental design for a tote bag, as shown and described.
FIG. 1 is a bottom plan view of a tote bag showing my new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a perspective view thereof shown in an alternate and folded position;
FIG. 4 is a top plan view thereof shown in an alternate and folded position; and,
FIG. 5 is a perspective view, showing the claimed design in use.
The broken line showings of a tote bag in FIG. 5 are for the purpose of illustrating the environment in which the design is associated and form no part of the claimed design.