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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def go_to(self, x, y, z=DEFAULT, velocity=DEFAULT):
 """ Go to a position :param x: X coordinate :param y: Y coordinate :param z: Z coordinate :param velocity: the velocity (meters/second) :return: """


        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