Python: How to throw an exception as soon as the user presses a certain specific key (other than ctrl + c)

Question

I'm using selenium on Python and, I wish I could interrupt the program, catch the exception and do something with it, as soon as the user presses a certain specific key (other than ctrl + c ,because I've already cought this exception). Do you think it is possible ?

As an exemple: I would like to convert a text to speech with selenium by using this website: "https://www.naturalreaders.com/online" (I already did it) and then, when the user presses (for exemple) the space key, I would like to pause the speech (and resume the speech if the user presses this key again)

here is my code:

from selenium import webdriver
from selenium.webdriver import ActionChains
from selenium.webdriver.common.by import By
from selenium.common.exceptions import NoSuchElementException
from selenium.common.exceptions import StaleElementReferenceException
from selenium.webdriver.support import expected_conditions
from selenium.webdriver.support.ui import WebDriverWait

from bs4 import BeautifulSoup
from ebooklib import epub
from colorama import Fore, Style
import time, logging, ebooklib, os


if "__main__" == __name__:
    
    def load_site(url, silent= False):
        #those four varables are inside this function
        global driver, r_click, wait, ignored_exceptions
        #close all Chrome windows before starting
        os.system("taskkill /f /im chrome.exe 2> nul")
        
        #this is if I would like to connect to the google account
        chr_options = webdriver.ChromeOptions()
        if silent:
            #to run a site in the background
            chr_options.add_argument("headless")
        driver = webdriver.Chrome(executable_path= <were it is located on your device>, options= chr_options)
        driver.delete_all_cookies()
        driver.get(url)
        #this is a called function which wait until an element is clickable on the driver...
        wait = WebDriverWait(driver, 20,ignored_exceptions=ignored_exceptions)
        driver.maximize_window();time.sleep(1)

    def connect_voice(driver):
        #here I choose the voice on the site inside the driver
        global wait      
        speakers = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[3]"))).click()
        free = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/div[2]/div[2]/div/div/div/app-voice-list/div/mat-tab-group/mat-tab-header/div[2]/div/div/div[1]"))).click(); time.sleep(0.5)
        Paul = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/div[2]/div[2]/div/div/div/app-voice-list/div/mat-tab-group/div/mat-tab-body[1]/div/app-voice/div/mat-selection-list/mat-list-option[6]/div/div[2]/div/div[2]/div/div"))).click()
    
    def say(text, WPM = 180,to_print= False):
        global driver
        nb_words = len(text.split())
        if nb_words == 0: return None
        
        #I replace this character for a good prononciation
        text = list(text.replace("—", "-"))
        #here I delete all the useless numbers of the text
        for i in range(len(text)-1):
            num = 1
            while i + num < len(text) and text[i].isalpha() and text[i+num].isnumeric():          
                text[i+num] = ""
                num += 1
        text = "".join(text)
        
        #here I calculate the good speed for printting a letter
        LPM = (len(text) * WPM) / nb_words
        SPL = (1 / LPM) * 60 - 0.015
        
        #I don't forget to delete the previous text
        clear = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-home/div/app-input/div/div/div[1]/div[2]/button[5]"))); ActionChains(driver).move_to_element(clear).click(clear).perform()
        #and I paste the actual text on the site
        paste = wait.until(expected_conditions.presence_of_element_located((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-home/div/app-input/div/div/div[2]"))).send_keys(text)
        #here I play the text, and he read it  
        play = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[1]"))).click()
        time.sleep(0.6)
        for i, l in enumerate(text):
            #Here I color all the upper characters in upper words
            if l.isupper() and (i == len(text)-1 or text[i+1].isupper() or text[i+1] in [" ", ".", ";",",",":","!","(",")","-"]):
                l = f"{c2}{l}{reset}"
            print(l, end= ""); time.sleep(SPL)
        print()

    logging.captureWarnings(True)
    #colors for the print function
    c1 = Style.BRIGHT + Fore.YELLOW
    c2 = Style.BRIGHT + Fore.CYAN
    reset_color = Style.RESET_ALL
    ignored_exceptions =(NoSuchElementException,StaleElementReferenceException,)
    
    #the site is a text to speech converter
    load_site("https://www.naturalreaders.com/online/", silent= True)
    print("starting reading...")
    connect_voice(driver)
    
    #I read a book which is downloaded on my device
    book = epub.read_epub(<path of the epub book>)
    #get the item objects corresponding to all chapters
    book = list(book.get_items_of_type(ebooklib.ITEM_DOCUMENT))
    #for each item
    for chap in book[1:]:
        try:
            #I get only the text of the html code
            soup = BeautifulSoup(chap.get_content(), "lxml")
            if soup is not None:
                texte = soup.text.splitlines()
                for line in texte:
                    #and I read it line by line
                    say(line + ' ', to_print= True)
        except KeyboardInterrupt:
            #If the user click on ctrl + c, the program read the next chapter
            #(but before, I just pause the actual reading)                         
            play = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[2]"))).click()
            
        print('\n\n')

I would like to add a try/except inside the say function, whose purpose is to stop temporarily the reading when the user click on a specific key (maybe F7, or a key not too accessible) or stop the reading by holding an accesible key(a space). Does anyone is in a situation similar to mine or knows how to raise an exception by clicking or holding a key (other than ctrl + c because already used)?

Answer 1

I just found how to do it:

import keyboard
for i, l in enumerate(sent):
    if keyboard.is_pressed('p'):
        pause = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[2]"))).click(); time.sleep(0.5)
        while not(keyboard.is_pressed('p')):
             time.sleep(0.05)                
        play = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[1]"))); ActionChains(driver).move_to_element(pause).click(pause).perform()
        id_sent -= 1; break
   if l.isupper() and (i == len(sent)-1 or sent[i+1].isupper() or sent[i+1] in [" ", ".", ";",",",":","!","(",")","-"]):
       l = f"{c2}{l}{reset}"
   print(l, end= ""); time.sleep(SPL)

like you have seen, I added this part of code inside the for loop:

if keyboard.is_pressed('p') #do someting
    pause = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[2]"))).click()
    time.sleep(0.5) #it is important, because if you don't set a sleep, the while loup will be True directly  
    while not(keyboard.is_pressed('p')): #we wait for the user to press this key again, to do an other thing
         time.sleep(0.05)            
    play = wait.until(expected_conditions.element_to_be_clickable((By.XPATH,"/html/body/app-root/div/app-main/mat-sidenav-container/mat-sidenav-content/app-header/mat-toolbar/div[2]/div[2]/app-reader/div/button[1]"))); ActionChains(driver).move_to_element(pause).click(pause).perform()

the condition: if keyboard.is_pressed('p') ; doesn't wait for you to press the 'p' key, so the for loop continue (that's why you need to put this condition inside a for loop, because if you don't, the condition could be true, but already executed and already returned False)