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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 Classifier object from a json dictionary."""

        args = {}
        if 'classifier_id' in _dict:
            args['classifier_id'] = _dict.get('classifier_id')
        else:
            raise ValueError(
                'Required property \'classifier_id\' not present in Classifier JSON'
            )
        if 'name' in _dict:
            args['name'] = _dict.get('name')
        else:
            raise ValueError(
                'Required property \'name\' not present in Classifier JSON')
        if 'owner' in _dict:
            args['owner'] = _dict.get('owner')
        if 'status' in _dict:
            args['status'] = _dict.get('status')
        if 'core_ml_enabled' in _dict:
            args['core_ml_enabled'] = _dict.get('core_ml_enabled')
        if 'explanation' in _dict:
            args['explanation'] = _dict.get('explanation')
        if 'created' in _dict:
            args['created'] = string_to_datetime(_dict.get('created'))
        if 'classes' in _dict:
            args['classes'] = [
                Class._from_dict(x) for x in (_dict.get('classes'))
            ]
        if 'retrained' in _dict:
            args['retrained'] = string_to_datetime(_dict.get('retrained'))
        if 'updated' in _dict:
            args['updated'] = string_to_datetime(_dict.get('updated'))
        return cls(**args)