The small farmyard uses traditional stone mills as grain processing tools to attract customers. A customer walks 20 times along a circle with a radius of 1 meter. How many meters has he walked?
农家小院用传统的石磨作为粮食加工工具吸引顾客，一位顾客沿着半径为1米的圆形推磨，走了20圈，大约走了多少米？
<gadget id="calculator">2 * 3.14 * 1 * 20</gadget>
<output>125.6</output>

<result>125.6</result>