使用

input('Enter your input:')

如果你使用Python 3。
如果你想得到一个数值，只需转换它：

try:
    mode = int(input('Input:'))
except ValueError:
    print("Not a number")

如果使用Python 2，则需要使用raw_input而不是input。

看起来你在这里混合了不同的Python（Python 2.x与Python 2.x）。Python 3.x）.这基本上是正确的：

nb = input('Choose a number: ')

问题是它只在Python 3中支持。正如@sharpner回答的那样，对于旧版本的Python（2.x），您必须使用函数raw_input：

nb = raw_input('Choose a number: ')

如果你想把它转换成一个数字，那么你应该试试：

number = int(nb)

...但你需要考虑到这可能会引发异常：

try:
    number = int(nb)
except ValueError:
    print("Invalid number")

如果你想使用格式化打印数字，在Python 3中推荐使用str.format()：

print("Number: {0}\n".format(number))

而不是：

print('Number %s \n' % (nb))

但是这两个选项（str.format()和%）在Python 2.7和Python 3中都可以工作。

非阻塞多线程示例：

由于阻止键盘输入（因为input()函数阻止）通常不是我们想要做的（我们经常想继续做其他事情），这里有一个非常精简的多线程示例来演示如何继续运行您的主应用程序，同时仍然在键盘输入到达时阅读它们。我在eRCaGuy_PyTerm串行终端程序here (search the code for input() )中使用了这种技术。
其工作原理是创建一个在后台运行的线程，不断调用input()，然后将其接收到的任何数据传递到队列。
这样，主线程就可以做它想做的任何事情，只要队列中有东西，就从第一个线程接收键盘输入数据。

1. Python 3裸代码示例（无注解）：

import threading
import queue
import time

def read_kbd_input(inputQueue):
    print('Ready for keyboard input:')
    while (True):
        input_str = input()
        inputQueue.put(input_str)

def main():
    EXIT_COMMAND = "exit"
    inputQueue = queue.Queue()

    inputThread = threading.Thread(target=read_kbd_input, args=(inputQueue,), daemon=True)
    inputThread.start()

    while (True):
        if (inputQueue.qsize() > 0):
            input_str = inputQueue.get()
            print("input_str = {}".format(input_str))

            if (input_str == EXIT_COMMAND):
                print("Exiting serial terminal.")
                break
            
            # Insert your code here to do whatever you want with the input_str.

        # The rest of your program goes here.

        time.sleep(0.01) 
    print("End.")

if (__name__ == '__main__'): 
    main()

2.与上面相同的Python 3代码，但有大量的解释性注解：

"""
read_keyboard_input.py

Gabriel Staples
www.ElectricRCAircraftGuy.com
14 Nov. 2018

References:
- https://pyserial.readthedocs.io/en/latest/pyserial_api.html
- *****https://www.tutorialspoint.com/python/python_multithreading.htm
- *****https://en.wikibooks.org/wiki/Python_Programming/Threading
- https://stackoverflow.com/questions/1607612/python-how-do-i-make-a-subclass-from-a-superclass
- https://docs.python.org/3/library/queue.html
- https://docs.python.org/3.7/library/threading.html

To install PySerial: `sudo python3 -m pip install pyserial`

To run this program: `python3 this_filename.py`

"""

import threading
import queue
import time

def read_kbd_input(inputQueue):
    print('Ready for keyboard input:')
    while (True):
        # Receive keyboard input from user.
        input_str = input()
        
        # Enqueue this input string.
        # Note: Lock not required here since we are only calling a single Queue method, not a sequence of them 
        # which would otherwise need to be treated as one atomic operation.
        inputQueue.put(input_str)

def main():

    EXIT_COMMAND = "exit" # Command to exit this program

    # The following threading lock is required only if you need to enforce atomic access to a chunk of multiple queue
    # method calls in a row.  Use this if you have such a need, as follows:
    # 1. Pass queueLock as an input parameter to whichever function requires it.
    # 2. Call queueLock.acquire() to obtain the lock.
    # 3. Do your series of queue calls which need to be treated as one big atomic operation, such as calling
    # inputQueue.qsize(), followed by inputQueue.put(), for example.
    # 4. Call queueLock.release() to release the lock.
    # queueLock = threading.Lock() 

    #Keyboard input queue to pass data from the thread reading the keyboard inputs to the main thread.
    inputQueue = queue.Queue()

    # Create & start a thread to read keyboard inputs.
    # Set daemon to True to auto-kill this thread when all other non-daemonic threads are exited. This is desired since
    # this thread has no cleanup to do, which would otherwise require a more graceful approach to clean up then exit.
    inputThread = threading.Thread(target=read_kbd_input, args=(inputQueue,), daemon=True)
    inputThread.start()

    # Main loop
    while (True):

        # Read keyboard inputs
        # Note: if this queue were being read in multiple places we would need to use the queueLock above to ensure
        # multi-method-call atomic access. Since this is the only place we are removing from the queue, however, in this
        # example program, no locks are required.
        if (inputQueue.qsize() > 0):
            input_str = inputQueue.get()
            print("input_str = {}".format(input_str))

            if (input_str == EXIT_COMMAND):
                print("Exiting serial terminal.")
                break # exit the while loop
            
            # Insert your code here to do whatever you want with the input_str.

        # The rest of your program goes here.

        # Sleep for a short time to prevent this thread from sucking up all of your CPU resources on your PC.
        time.sleep(0.01) 
    
    print("End.")

# If you run this Python file directly (ex: via `python3 this_filename.py`), do the following:
if (__name__ == '__main__'): 
    main()

输出示例：

$python3 read_keyboard_input.py
准备好键盘输入：
嘿
input_str = hey
你好
input_str = hello
7000
输入字符串= 7000
出口
input_str = exit
正在退出串行终端。
端

Python Queue库是线程安全的：

请注意，Queue.put()和Queue.get()以及其他Queue类方法都是线程安全的！（这与C++中标准模板库中的队列和其他容器不同！由于Python Queue类及其方法是线程安全的，这意味着它们实现了线程间操作所需的所有内部锁定语义，因此队列类中的每个函数调用都可以被视为单个原子操作。请参阅文档顶部的注解：https://docs.python.org/3/library/queue.html（重点已添加）：
队列模块实现多生产者、多消费者队列。在线程编程中，当信息必须在多个线程之间安全交换时，它特别有用。本模块中的Queue类实现了所有需要的锁定语义。

参考资料：

1. https://pyserial.readthedocs.io/en/latest/pyserial_api.html
   1.* https://www.tutorialspoint.com/python/python_multithreading.htm
   1.* https://en.wikibooks.org/wiki/Python_Programming/Threading
2. Python: How do I make a subclass from a superclass?
3. https://docs.python.org/3/library/queue.html
4. https://docs.python.org/3.7/library/threading.html
   1.[我的仓库，我使用上面介绍的技术和代码] https://github.com/ElectricRCAircraftGuy/eRCaGuy_PyTerm

相关/交联：

1.[我的回答] PySerial非阻塞读循环

你可以简单地通过使用一个变量来使用input（）函数。快速的例子！

user = input("Enter any text: ")
print(user)

我来这里是为了学习如何读一个字。
我找到了readchar库，基于this question的答案。pip安装后：

import readchar

key = readchar.readkey()