Initialize a Classification object from a json dictionary.

def _from_dict(cls, _dict):
        """Initialize a Classification object from a json dictionary."""
        args = {}
        if 'classifier_id' in _dict:
            args['classifier_id'] = _dict.get('classifier_id')
        if 'url' in _dict:
            args['url'] = _dict.get('url')
        if 'text' in _dict:
            args['text'] = _dict.get('text')
        if 'top_class' in _dict:
            args['top_class'] = _dict.get('top_class')
        if 'classes' in _dict:
            args['classes'] = [
                ClassifiedClass._from_dict(x) for x in (_dict.get('classes'))
            ]
        return cls(**args)