i dont understand the difference between the index: and :index and also these-> for index in range(len(other.cont)

Question

class SpecialString:
def __init__(self, cont):
self.cont = cont

def __gt__(self, other):
for index in range(len(other.cont)+1):
result = other.cont[:index] + ">" + self.cont
result += ">" + other.cont[index:]
print(result)

spam = SpecialString("spam")
eggs = SpecialString("eggs")
spam > eggs

Answer 1

The difference between [:index] & [index:] is

Let's say that you have a string ="hello"
And you but this

Print(string[2:4]) // the output will be (ll)
Because you put the start index and end index. [start:end]

If you typed like this
Print(string[:4]) // the output will be (hell)
Which means [start from 0:end with 4]

If you typed like this
Print(string[2:]) // the output will be (llo)
Which means [start from 2:end with the last character]