remove useless mention to another ex

piscine/week03/day04/ex02/README.md

@@ -1,6 +1,6 @@
 # Exerice 2: Punctuation
 
-The goal of this exerice is to learn to deal with punctuation. In Natural Language Processing, some basic approaches as Bag of Words (exercise X) model the text as an unordered combination of words. In that case the punctuation is not always useful as it doesn't add information to the model. That is why is removed. 
+The goal of this exerice is to learn to deal with punctuation. In Natural Language Processing, some basic approaches as Bag of Words model the text as an unordered combination of words. In that case the punctuation is not always useful as it doesn't add information to the model. That is why is removed. 
 
 1. Remove the punctuation from this sentence. All characters in !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~ are considered as punctuation.
 
@@ -8,4 +8,4 @@ The goal of this exerice is to learn to deal with punctuation. In Natural Langua
 
     Remove, this from .? the sentence !!!! !"#&'()*+,-./:;<=>_
 
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+    ```