def from_stream(cls, stream):
        """
        Extract data from stream. Returns None if some error occurred.
        """
        cycles = []
        while True:
            scf_cycle = GroundStateScfCycle.from_stream(stream)
            if scf_cycle is None: break
            cycles.append(scf_cycle)

        return cls(cycles) if cycles else None
Extract data from stream. Returns None if some error occurred.