code: def _freezer_lookup(freezer_string):
      
      sanitized = freezer_string.lower().strip()
      for freezer in FREEZER.ALL:
          freezer_instance = freezer()
          freezer_name = six.text_type(freezer_instance)
          if freezer_name == six.text_type(sanitized):
              return freezer
      else:
          if sanitized != freezer_string:
              raise ValueError(u"Unsupported freezer type \"{0}\". (Sanitized to \"{1}\")".format(freezer_string,
                                                                                                sanitized))
          else:
              raise ValueError(u"Unsupported freezer type \"{0}\".".format(freezer_string))
docs: Translate a string that may be a freezer name into the internal freezer constant
  
      :param freezer_string
      :return: