java调用时，不能在python中运行raw_input

Question

我想用run.exec在java代码中执行python，并期望用户在python中输入。当我在intelliJ中运行java时，它无法获取输入并且什么都不打印。作为代码：

input.py：

def input():
    print "hello"
    w=int(raw_input('input weight:'))
    h=int(raw_input('input height:'))
    s=w*h
    print s
if __name__=='__main__':
    print 'main'
    input()

java代码：

Process pr = Runtime.getRuntime().exec("python input.py");
            InputStream is = pr.getInputStream();
            BufferedReader stdError = new BufferedReader(new InputStreamReader(pr.getErrorStream()));
            String line;          
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            while ((line = br.readLine()) != null) {

                System.out.println(line);
            }
            while ((line=stdError.readLine())!=null){
                System.out.println(line);
            }

            pr.waitFor();