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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_database_args(parser):
    '''
    Add a standard set of database arguments for argparse
    '''
    parser.add_argument(
        'url',
        nargs='?',
        default='sqlite:///ncbi_taxonomy.db',
        type=sqlite_default(),
        help=('Database string URI or filename.  If no database scheme '
              'specified \"sqlite:///\" will be prepended. [%(default)s]'))
    db_parser = parser.add_argument_group(title='database options')

    # TODO: better description of what --schema does
    db_parser.add_argument(
        '--schema',
        help=('Name of SQL schema in database to query '
              '(if database flavor supports this).'))

    return parser