I claim the ornamental design for a basketball court, as shown and described.
FIG. 1 is a top plan view showing my new design for a basketball court; and,
FIG. 2 is an enlarged view of the portion of FIG. 1 indicated by circle 2.
The central circular broken line shown in FIG. 1 is included for the purpose of illustrating a feature of the basketball court that forms no part of the claimed design.