The ornamental design for a container, as shown and described.
FIG. 1 is a front perspective view of the container of my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a right side view thereof; the left side view being a mirror image thereof;
FIG. 5 is a top view thereof; and,
FIG. 6 is a bottom view thereof.
The photographs of the design include, in the transparent lower part of the container, dark portions that are internal reflections. The internal reflections within the lower part of the container are not part of the claimed invention.