code: def _filter_by_zoom(element=None, conf_string=None, zoom=None):
      
      for op_str, op_func in [
          # order of operators is important:
          # prematurely return in cases of "<=" or ">=", otherwise
          # _strip_zoom() cannot parse config strings starting with "<"
          # or ">"
          ("=", operator.eq),
          ("<=", operator.le),
          (">=", operator.ge),
          ("<", operator.lt),
          (">", operator.gt),
      ]:
          if conf_string.startswith(op_str):
              return element if op_func(zoom, _strip_zoom(conf_string, op_str)) else None
docs: Return element only if zoom condition matches with config string.