code: def go_to(self, x, y, z=DEFAULT, velocity=DEFAULT):
          
  
          z = self._height(z)
  
          dx = x - self._x
          dy = y - self._y
          dz = z - self._z
          distance = math.sqrt(dx * dx + dy * dy + dz * dz)
  
          duration_s = distance / self._velocity(velocity)
          self._hl_commander.go_to(x, y, z, 0, duration_s)
          time.sleep(duration_s)
  
          self._x = x
          self._y = y
          self._z = z
docs: Go to a position
  
          :param x: X coordinate
          :param y: Y coordinate
          :param z: Z coordinate
          :param velocity: the velocity (meters/second)
          :return: