驗證碼功能：

def get_img(request):
    import random
    def get_random_img():
        return (random.randint(0,255),random.randint(0,255),random.randint(0,255))

    from PIL import Image,ImageDraw,ImageFont
    img = Image.new("RGB",(270,40),color=get_random_img())
    #方式二
    # with open('valid_code.png','wb') as f:
 

    #     img.save(f)
    #
    # with open('valid_code.png','rb') as f:
    #     data = f.read()

    from io import BytesIO

    draw = ImageDraw.Draw(img)
    chandan_ttf = ImageFont.truetype("static/font/chandan.ttf",size=32)

    for i in range(0,5):
        num = str(random.randint(0,9))              #
 
生成隨機數字
        upper_alpha = chr(random.randint(65,90))    #生成隨機大寫字母
        low_alpha = chr(random.randint(97,122))     #生成隨機小寫字母
        now_char = random.choice([num,upper_alpha,low_alpha])   #使用隨機列表從中選擇

        draw.text((i*50,5),now_char,get_random_img(),font=chandan_ttf)      #draw.text(xy座標，寫的內容text，背景顏色，字型ttf)
 


    f = BytesIO()
    img.save(f,"png")
    data = f.getvalue()


    return HttpResponse(data)