code: def where(self, cond, value, other=None, subset=None, **kwargs):
          
  
          if other is None:
              other = ''
  
          return self.applymap(lambda val: value if cond(val) else other,
                               subset=subset, **kwargs)
docs: 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