code: def _view_axes(E, R, V, roll):
      """
      Get the unit viewing axes in data coordinates.
  
      Parameters
      ----------
      E : 3-element numpy array
          The coordinates of the eye/camera.
      R : 3-element numpy array
          The coordinates of the center of the view box.
      V : 3-element numpy array
          Unit vector in the direction of the vertical axis.
      roll : float
          The roll angle in radians.
  
      Returns
      -------
      u : 3-element numpy array
          Unit vector pointing towards the right of the screen.
      v : 3-element numpy array
          Unit vector pointing towards the top of the screen.
      w : 3-element numpy array
          Unit vector pointing out of the screen.
      """
      w = E - R
      w = w / np.linalg.norm(w)
      u = np.cross(V, w)
      u = u / np.linalg.norm(u)
      v = np.cross(w, u)  # Will be a unit vector
  
      # Save some computation for the default roll=0
      if roll != 0:
          # A positive rotation of the camera is a negative rotation of the world
          Rroll = _rotation_about_vector(w, -roll)
          u = np.dot(Rroll, u)
          v = np.dot(Rroll, v)
      return u, v, w
  
imports: import numpy
  from matplotlib import _api
label_desc: Use image node_id 4 for calling a global function with example usage: _view_axes(E, R, V, roll) and returns: u,  v,  w