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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_to_dict(session, recursive, back_references, include_defaults):
 """Exports databases and druid clusters to a dictionary"""

    logging.info('Starting export')
    dbs = session.query(Database)
    databases = [database.export_to_dict(recursive=recursive,
                 include_parent_ref=back_references,
                 include_defaults=include_defaults) for database in dbs]
    logging.info('Exported %d %s', len(databases), DATABASES_KEY)
    cls = session.query(DruidCluster)
    clusters = [cluster.export_to_dict(recursive=recursive,
                include_parent_ref=back_references,
                include_defaults=include_defaults) for cluster in cls]
    logging.info('Exported %d %s', len(clusters), DRUID_CLUSTERS_KEY)
    data = dict()
    if databases:
        data[DATABASES_KEY] = databases
    if clusters:
        data[DRUID_CLUSTERS_KEY] = clusters
    return data