The ornamental design for a papercartridge for a printer, as shown and described.
FIG. 1 is a perspective view of a paper cartridge for a printer;
FIG. 2 is a front view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a right-side view thereof;
FIG. 5 is a left-side view thereof;
FIG. 6 is a rear view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is a reduced top view thereof in an unfolded and open position; and,
FIG. 9 is another reduced top view thereof in an unfolded and open position including the folding lines.
The phantom line immediately adjacent the claimed edge on one side of the unclaimed rectangular feature in FIGS. 7-9 represents the boundaries of the claimed design. The dot-chain lines in FIG. 9 illustrate fold lines and form no part of the claimed design. The dashed lines in the figures illustrate the portions of the design that form no part of the claimed design. None of the broken lines form any part of the claimed design.