Initialize a SupportedFeatures object from a json dictionary.

def _from_dict(cls, _dict):
        """Initialize a SupportedFeatures object from a json dictionary."""
        args = {}
        if 'custom_language_model' in _dict:
            args['custom_language_model'] = _dict.get('custom_language_model')
        else:
            raise ValueError(
                'Required property \'custom_language_model\' not present in SupportedFeatures JSON'
            )
        if 'speaker_labels' in _dict:
            args['speaker_labels'] = _dict.get('speaker_labels')
        else:
            raise ValueError(
                'Required property \'speaker_labels\' not present in SupportedFeatures JSON'
            )
        return cls(**args)