def list_ifd(self):
        """Return the list of IFDs in the header."""
        i = self._first_ifd()
        ifds = []
        while i:
            ifds.append(i)
            i = self._next_ifd(i)
        return ifds
def list_ifd ( self ) : i = self . _first_ifd ( ) ifds = [ ] while i : ifds . append ( i ) i = self . _next_ifd ( i ) return ifds
Return the list of IFDs in the header.