[Tutor] Slicing index

[Carlene Wong]

Hello, I’m new but I’m getting trouble with slicing an index into another.
Eg. Def mysentence (sentence, old, new)
 If old in sentence[-4:]:
n= sentence.index(old)
newsent=Sentence [:n]+new
return newsent
return mysentence
print(mysentence(“Hello there, it’s raining cats and cats”, “ cats”, “ dogs“)

It keeps printing
Hello there, it’s raining dogs

Your help

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