code: def _match(self, x, op, y):
          
          if (op not in self.condition_mapper):
              raise ValueError('Invalid where condition given')
  
          func = getattr(self, self.condition_mapper.get(op))
          return func(x, y)
docs: Compare the given `x` and `y` based on `op`
  
          :@param x, y, op
          :@type x, y: mixed
          :@type op: string
  
          :@return bool
          :@throws ValueError