Electronic keyboard musical instrument

Abstract

CLAIM The ornamental design for an electronic keyboard musical instrument, as shown. DESCRIPTION FIG. 1 is a top view of an electronic keyboard musical instrument; FIG. 2 is a front view thereof; FIG. 3 is a rear view thereof; FIG. 4 is a bottom view thereof; FIG. 5 is a left-side view thereof; and, FIG. 6 is a right-side view thereof.