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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _from_dict(cls, _dict):
 """Initialize a DetectedFaces object from a json dictionary."""

        args = {}
        if 'images_processed' in _dict:
            args['images_processed'] = _dict.get('images_processed')
        else:
            raise ValueError(
                'Required property \'images_processed\' not present in DetectedFaces JSON'
            )
        if 'images' in _dict:
            args['images'] = [
                ImageWithFaces._from_dict(x) for x in (_dict.get('images'))
            ]
        else:
            raise ValueError(
                'Required property \'images\' not present in DetectedFaces JSON'
            )
        if 'warnings' in _dict:
            args['warnings'] = [
                WarningInfo._from_dict(x) for x in (_dict.get('warnings'))
            ]
        return cls(**args)