```py
        >>> from datasets import load_dataset
        >>> ds = load_dataset("rotten_tomatoes", split="train", streaming=True)
        >>> def add_prefix(example):
        ...     example["text"] = "Review: " + example["text"]
        ...     return example
        >>> ds = ds.map(add_prefix)
        >>> list(ds.take(3))
        [{'label': 1,
         'text': 'Review: the rock is destined to be the 21st century\'s new " conan " and that he\'s going to make a splash even greater than arnold schwarzenegger , jean-claud van damme or steven segal .'},
         {'label': 1,
         'text': 'Review: the gorgeously elaborate continuation of " the lord of the rings " trilogy is so huge that a column of words cannot adequately describe co-writer/director peter jackson\'s expanded vision of j . r . r . tolkien\'s middle-earth .'},
         {'label': 1, 'text': 'Review: effective but too-tepid biopic'}]
        ```
        """
        if isinstance(input_columns, str):