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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 to_file_async(self, destination, format='csv', csv_delimiter=',', csv_header=True):
 """Start saving the results to a local file in CSV format and return a Job for completion. Args: destination: path on the local filesystem for the saved results. format: the format to use for the exported data; currently only 'csv' is supported. csv_delimiter: for CSV exports, the field delimiter to use. Defaults to ',' csv_header: for CSV exports, whether to include an initial header line. Default true. Returns: A Job for the async save operation. Raises: An Exception if the operation failed. """

    self.to_file(destination, format=format, csv_delimiter=csv_delimiter, csv_header=csv_header)