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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 del_key(self, key, key_to_delete):
        "Delete the `key_to_delete` for the record found with `key`."
        v = self.get(key)
        if key_to_delete in v:
            del v[key_to_delete]
            self.set(key, v)