docs: def _parse_binary(v, header_d):
      """ Parses binary string.
  
      Note:
          <str> for py2 and <binary> for py3.
  
      """
  
      # This is often a no-op, but it ocassionally converts numbers into strings
  
      v = nullify(v)
  
      if v is None:
          return None
  
      if six.PY2:
          try:
              return six.binary_type(v).strip()
          except UnicodeEncodeError:
              return six.text_type(v).strip()
      else:
          # py3
          try:
              return six.binary_type(v, 'utf-8').strip()
          except UnicodeEncodeError:
              return six.text_type(v).strip()