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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 save_report(self, file_path):
 """Write coveralls report to file."""

        try:
            report = self.create_report()
        except coverage.CoverageException as e:
            log.error('Failure to gather coverage:', exc_info=e)
        else:
            with open(file_path, 'w') as report_file:
                report_file.write(report)