def _from_dict(cls, _dict):
        """Initialize a RuntimeEntity object from a json dictionary."""
        args = {}
        if 'entity' in _dict:
            args['entity'] = _dict.get('entity')
        else:
            raise ValueError(
                'Required property \'entity\' not present in RuntimeEntity JSON'
            )
        if 'location' in _dict:
            args['location'] = _dict.get('location')
        else:
            raise ValueError(
                'Required property \'location\' not present in RuntimeEntity JSON'
            )
        if 'value' in _dict:
            args['value'] = _dict.get('value')
        else:
            raise ValueError(
                'Required property \'value\' not present in RuntimeEntity JSON')
        if 'confidence' in _dict:
            args['confidence'] = _dict.get('confidence')
        if 'metadata' in _dict:
            args['metadata'] = _dict.get('metadata')
        if 'groups' in _dict:
            args['groups'] = [
                CaptureGroup._from_dict(x) for x in (_dict.get('groups'))
            ]
        return cls(**args)