code: def unpack(self, source: IO):
          
          self.access_flags.unpack(source.read(2))
          self._name_index, self._descriptor_index = unpack('>HH', source.read(4))
          self.attributes.unpack(source)
docs: Read the Field from the file-like object `fio`.
  
          .. note::
  
              Advanced usage only. You will typically never need to call this
              method as it will be called for you when loading a ClassFile.
  
          :param source: Any file-like object providing `read()`