code: def earth_accel2_df(IMU,IMU2,ATT):
      '''return earth frame acceleration vector from df log'''
      r = rotation_df(ATT)
      accel1 = Vector3(IMU.AccX, IMU.AccY, IMU.AccZ)
      accel2 = Vector3(IMU2.AccX, IMU2.AccY, IMU2.AccZ)
      accel = 0.5 * (accel1 + accel2)
      return r * accef earth_accel2_df(IMU,IMU2,ATT):
      '''return earth frame acceleration vector from df log'''
      r = rotation_df(ATT)
      accel1 = Vector3(IMU.AccX, IMU.AccY, IMU.AccZ)
      accel2 = Vector3(IMU2.AccX, IMU2.AccY, IMU2.AccZ)
      accel = 0.5 * (accel1 + accel2)
      return r * accel
docs: return earth frame acceleration vector from df log