from __future__ import division
import serial, struct, time
#def move(servo,value):
#    if value > 254: value=254
#    ser.write(struct.pack("BBB",255,servo,value))

def move(servo,value):
    pos=value*5000/256 +500
    ser.write(struct.pack("BBBBBB",128,1,4,servo,pos//128,pos%128))

def flat():
    move(0,128)
    move(1,128)
    move(2,128)

def bridge():
    move(0,60)
    move(1,128)
    move(2,60)

def curl():
    move(0,255)
    move(1,0)
    move(2,255)

def rear():
    move(2,128)
    move(1,0)
    move(0,0)

ser=serial.Serial("COM3")
try:
    curl()
    for i in range(256,0,-1):
        move(0,i)
        move(0,i)
    for i in range(0,256):
        move(0,i)
        move(0,i)

    for i in range(5):
      bridge()
      time.sleep(0.5)
      flat()
      time.sleep(0.5)
    rear()
    time.sleep(5)
finally:
    ser.close()
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