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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 write(self, data, method='w'):
 """ Export data to CSV file. :param data: Either a list of tuples or a list of lists. :param method: File opening method. """

        # Create list of lists from flat list
        data = data if isinstance(data[0], (list, set, tuple)) else [[d] for d in data]

        # Open file and write rows
        with open(self.file_path, method) as write:
            wr = csv_builtin.writer(write)
            wr.writerows(data)
        return self.file_path