'load(filething)
Args:
filething (filething)
Raises:
mutagen.MutagenError'

@convert_error(IOError, error)
@loadfile()
def load(self, filething):

    fileobj = filething.fileobj
    self.info = ASFInfo()
    self.tags = ASFTags()
    self._tags = {}
    self._header = HeaderObject.parse_full(self, fileobj)
    for guid in [ContentDescriptionObject.GUID, ExtendedContentDescriptionObject.GUID, MetadataObject.GUID, MetadataLibraryObject.GUID]:
        self.tags.extend(self._tags.pop(guid, []))
    assert (not self._tags)
