def get_statement_by_name(stmt_name):
    """Get a statement class given the name of the statement class."""
    stmt_classes = get_all_descendants(Statement)
    for stmt_class in stmt_classes:
        if stmt_class.__name__.lower() == stmt_name.lower():
            return stmt_class
    raise NotAStatementName('\"%s\" is not recognized as a statement type!'
                            % stmt_name)
Get a statement class given the name of the statement class.