@classmethod
def _from_dict(cls, _dict):
    """Initialize a NormalizationOperation object from a json dictionary."""
    args = {}
    if 'operation' in _dict:
        args['operation'] = _dict.get('operation')
    if 'source_field' in _dict:
        args['source_field'] = _dict.get('source_field')
    if 'destination_field' in _dict:
        args['destination_field'] = _dict.get('destination_field')
    return cls(**args)
