Read the first occurrence of ScfCycle from stream.

        Returns:
            None if no `ScfCycle` entry is found.

def from_stream(cls, stream):
        """
        Read the first occurrence of ScfCycle from stream.

        Returns:
            None if no `ScfCycle` entry is found.
        """
        fields = _magic_parser(stream, magic=cls.MAGIC)

        if fields:
            fields.pop("iter")
            return cls(fields)
        else:
            return None