code: def pxfrm2(frame_from, frame_to, etfrom, etto):
      
      frame_from = stypes.stringToCharP(frame_from)
      frame_to = stypes.stringToCharP(frame_to)
      etfrom = ctypes.c_double(etfrom)
      etto = ctypes.c_double(etto)
      outmatrix = stypes.emptyDoubleMatrix()
      libspice.pxfrm2_c(frame_from, frame_to, etfrom, etto, outmatrix)
      return stypes.cMatrixToNumpy(outmatrix)
docs: Return the 3x3 matrix that transforms position vectors from one
      specified frame at a specified epoch to another specified
      frame at another specified epoch.
  
      http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/pxfrm2_c.html
  
      :param frame_from: Name of the frame to transform from.
      :type frame_from: str
      :param frame_to: Name of the frame to transform to.
      :type frame_to: str
      :param etfrom: Evaluation time of frame_from.
      :type etfrom: float
      :param etto: Evaluation time of frame_to.
      :type etto: float
      :return: A position transformation matrix from frame_from to frame_to
      :rtype: 3x3 Element Array of floats