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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 where(self, cond, value, other=None, subset=None, **kwargs):
 """ Apply a function elementwise, updating the HTML representation with a style which is selected in accordance with the return value of a function. .. versionadded:: 0.21.0 Parameters cond : callable ``cond`` should take a scalar and return a boolean value : str applied when ``cond`` returns true other : str applied when ``cond`` returns false subset : IndexSlice a valid indexer to limit ``data`` to *before* applying the function. Consider using a pandas.IndexSlice kwargs : dict pass along to ``cond`` Returns ------- self : Styler See Also -------- Styler.applymap """


        if other is None:
            other = ''

        return self.applymap(lambda val: value if cond(val) else other,
                             subset=subset, **kwargs)