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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add(self, entry):
 """Adds an entry"""

        if self.get(entry) is not None:
            return
        try:
            list = self.cache[entry.key]
        except:
            list = self.cache[entry.key] = []
        list.append(entry)