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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 add_mongo_config(app, simple_connection_string, mongo_uri, collection_name):
 """ Configure the application to use MongoDB. :param app: Flask application :param simple_connection_string: Expects host:port:database_name or database_name Mutally_exclusive with mongo_uri in https://docs.mongodb.com/manual/reference/connection-string/ Mutually exclusive with simple_connection_string (must be None) :param collection_name: The collection containing Sacred's runs :return: """

    if mongo_uri != (None, None):
        add_mongo_config_with_uri(app, mongo_uri[0], mongo_uri[1],
                                  collection_name)
        if simple_connection_string is not None:
            print("Ignoring the -m option. Overridden by "
                  "a more specific option (-mu).", file=sys.stderr)
    else:
        # Use the default value 'sacred' when not specified
        if simple_connection_string is None:
            simple_connection_string = "sacred"
        add_mongo_config_simple(app, simple_connection_string, collection_name)