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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 create_mongo_db(database_name, collection_name, initial_document):
 """Create a new database and collection by inserting one document."""

    response_dict = {}
    try:
        mongodb_client_url = getattr(settings, 'MONGODB_CLIENT',
                                 'mongodb://localhost:27017/')
        mc = MongoClient(mongodb_client_url,document_class=OrderedDict)

        db = mc[str(database_name)]
        collection = db[str(collection_name)]

        d = json.loads(initial_document, object_pairs_hook=OrderedDict)

        collection.save(d)

    except:
        # error connecting to mongodb
        response_dict['error'] = str(sys.exc_info())

    return response_dict