four.py

for i in lines:
    print(f"i: {i}")           // i: 72-77,20-77
    split = i.split(",")      
    print(f"split: {split}")   // split: ['72-77', '20-77']
    
    print(len(split))          // 2
    print(type(split))         // <class 'list'> 
    print(split[0])            // 72-77