def METHOD_NAME(cond):
    region = ast.scope.get()
    filename, lineno = get_src_loc()
    whileOp = ast.WhileOp(cond, ast.Location(filename, lineno))
    region.append(whileOp)
    ast.scope.push(whileOp.body)
    def _exit_cb():
        ast.scope.pop()
    return WithScope(None, _exit_cb)