The ornamental design for a rotarypump, as shown and described.
FIG. 1 is a perspective view of a rotary pump showing my design;
FIG. 2 is a rear view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is a reference front view thereof; and,
FIG. 9 is a reference top plan view thereof.
The broken lines in the drawings are intended to show portions of the rotary pump that are not being claimed, and thus form no part of the claimed design