crnnport.py IndexError: tuple index out of range

[LuWei6896]

three is some errors on the below:
please input file name:1755.jpg
text_recs: [((16.0, 768.6111), (159.0, 790.30804)), ((48.0, 579.4411), (511.0, 690.03076)), ((528.0, 790.0657), (591.0, 800.4505))]
rec: ((16.0, 768.6111), (159.0, 790.30804))
pt1: (16.0, 768.6111)
pt2: (159.0, 790.30804)
Traceback (most recent call last):
File "demo.py", line 26, in
crnnRec(model,converter,img,text_recs)
File "/home/luwei/ML/CRNN/sceneReco-master/crnnport.py", line 57, in crnnRec
pt3 =(rec[6],rec[7])
IndexError: tuple index out of range

Q:waht is the fuction of this block?
pt3 =(rec[6],rec[7])
pt4 =(rec[4],rec[5])
partImg = dumpRotateImage(im,degrees(atan2(pt2[1]-pt1[1],pt2[0]-pt1[0])),pt1,pt2,pt3,pt4)
mahotas.imsave('%s.jpg'%index, partImg)

thanks for your contribution!
Best Reagrd!