def create_time_period_labels(connector):
    """
    This function writes the "time_period_labels" table to an sqlite
    database.

    Parameters
    ----------
    connector : sqlite3 connection object
        An object for connecting to a specific SQLite
        database.

    Returns
    -------
    table_command : string
        The command for generating the "time_period_labels" table.
    """

    table_command = """CREATE TABLE "time_period_labels" (
                	"t_period_labels"	text,
                	"t_period_labels_desc"	text,
                	PRIMARY KEY("t_period_labels")
                    );"""
    labels = [('e', 'existing vintages'), ('f', 'future vintages')]

    insert_command = """
                     INSERT INTO "time_period_labels" VALUES(?,?)
                     """

    cursor = connector.cursor()
    cursor.execute(table_command)
    cursor.executemany(insert_command, labels)
    connector.commit()

    return table_command