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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 ToneCategory object from a json dictionary."""

        args = {}
        if 'tones' in _dict:
            args['tones'] = [
                ToneScore._from_dict(x) for x in (_dict.get('tones'))
            ]
        else:
            raise ValueError(
                'Required property \'tones\' not present in ToneCategory JSON')
        if 'category_id' in _dict:
            args['category_id'] = _dict.get('category_id')
        else:
            raise ValueError(
                'Required property \'category_id\' not present in ToneCategory JSON'
            )
        if 'category_name' in _dict:
            args['category_name'] = _dict.get('category_name')
        else:
            raise ValueError(
                'Required property \'category_name\' not present in ToneCategory JSON'
            )
        return cls(**args)