code: def _filter_binding(self, binding):
          
          binding = binding.strip().split(" ", 1)[-1]  # isolate bind. from ISBN
          binding = remove_hairs_fn(binding)  # remove special chars from binding
  
          return binding.split(":")[-1].strip()
docs: Filter binding from ISBN record. In MARC XML / OAI, the binding
          information is stored in same subrecord as ISBN.
  
          Example:
              ``<subfield code="a">80-251-0225-4 (brož.) :</subfield>`` ->
              ``brož.``.