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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 export_obo(path_to_file, connection=None):
 """export database to obo file :param path_to_file: path to export file :param connection: connection string (optional) :return: """

    db = DbManager(connection)
    db.export_obo(path_to_export_file=path_to_file)
    db.session.close()