The ornamental design for a bag, as shown and described.
1. Bag
1.1: Perspective
1.2: Front
1.3: Back
1.4: Right
1.5: Left
1.6: Top
1.7: Bottom
1.8: Perspective second configuration
1.9: Perspective third configuration
The bag comprises a substantially parallelepiped-shaped body with a flat base and with an upper edge and middle edge made of fur or the like; two parallel bands are sewn vertically to the front and back side of the bag, from the base to the intermediate edge, from which they are folded and their longitudinal edges are sewn together forming the two handles of the bag; near the upper edge, at the center of the front and back walls, the body of the bag is provided with the male and female parts of a press stud for centrally closing the body opening; the male and female parts of two other press studs are provided on the sides of the body, enabling to reduce the size of the ends of said opening.