code: def R3(x: float):
      """Rotation matrix for ECI"""
      return np.array(
          [
              [np.cos(x), np.sin(x), 0],
              [-np.sin(x), np.cos(x), 0],
              [0, 0, 1],
          ]
      )
  
imports: from __future__ import annotations
  from datetime import datetime
  import numpy
  from .sidereal import greenwichsrt, juliandate
label_desc: Use image node_id 3 for calling a global function with example usage: R3(x) and returns: np