code: def col_apply(self, col, func, *args, **kwargs):
          
          if col in self.data:
              self.data[col] = self.data[col].apply(func, *args, **kwargs)
          else:
              self.meta[col] = self.meta[col].apply(func, *args, **kwargs)
docs: Apply a function to a column
  
          Parameters
          ----------
          col: string
              column in either data or metadata
          func: functional
              function to apply