Python3 动手自己写谷歌翻译（学员作品）

# /usr/bin/env python
# -*- coding: utf-8 -*-
import urllib.parse
import execjs,requests,termcolor

class Return_tk():

    def __init__(self):
        self.ctx = execjs.compile("""
        function TL(a) {
        var k = "";
        var b = 406644;
        var b1 = 3293161072;

        var jd = ".";
        var $b = "+-a^+6";
        var Zb = "+-3^+b+-f";

        for (var e = [], f = 0, g = 0; g < a.length; g++) {
            var m = a.charCodeAt(g);
            128 > m ? e[f++] = m : (2048 > m ? e[f++] = m >> 6 | 192 : (55296 == (m & 64512) && g + 1 < a.length && 56320 == (a.charCodeAt(g + 1) & 64512) ? (m = 65536 + ((m & 1023) << 10) + (a.charCodeAt(++g) & 1023),
            e[f++] = m >> 18 | 240,
            e[f++] = m >> 12 & 63 | 128) : e[f++] = m >> 12 | 224,
            e[f++] = m >> 6 & 63 | 128),
            e[f++] = m & 63 | 128)
        }
        a = b;
        for (f = 0; f < e.length; f++) a += e[f],
        a = RL(a, $b);
        a = RL(a, Zb);
        a ^= b1 || 0;
        0 > a && (a = (a & 2147483647) + 2147483648);
        a %= 1E6;
        return a.toString() + jd + (a ^ b)
    };

    function RL(a, b) {
        var t = "a";
        var Yb = "+";
        for (var c = 0; c < b.length - 2; c += 3) {
            var d = b.charAt(c + 2),
            d = d >= t ? d.charCodeAt(0) - 87 : Number(d),
            d = b.charAt(c + 1) == Yb ? a >>> d: a << d;
            a = b.charAt(c) == Yb ? a + d & 4294967295 : a ^ d
        }
        return a
    }
    """)

    def getTk(self, text):
        return self.ctx.call("TL", text)

def open_url(url):
    headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36'}
    req = requests.get(url=url, headers=headers)
    return req.content.decode('utf-8')

def max_length(content):
    if len(content) > 4891:
        print("翻译文本超过限制！")
        return

def print_result(parm):
    result = parm
    str_end = result.find("\",")
    if str_end > 4:
        print("翻译的结果为：",result[4:str_end])

def en_to_zn_translate(content, tk):
    max_length(content)
    content = urllib.parse.quote(content)
    #英译汉
    url = "http://translate.google.cn/translate_a/single?client=t" \
          "&sl=en&tl=zh-CN&hl=zh-CN&dt=at&dt=bd&dt=ex&dt=ld&dt=md&dt=qca" \
          "&dt=rw&dt=rm&dt=ss&dt=t&ie=UTF-8&oe=UTF-8&clearbtn=1&otf=1&pc=1" \
          "&srcrom=0&ssel=0&tsel=0&kc=2&tk=%s&q=%s" % (tk, content)
    result = open_url(url)
    print_result(result)

def zn_to_en_translate(content,tk):
    max_length(content)
    content = urllib.parse.quote(content)
    #汉译英
    url = "http://translate.google.cn/translate_a/single?client=t"\
          "&sl=zh-CN&tl=en&hl=zh-CN&dt=at&dt=bd&dt=ex&dt=ld&dt=md&dt=qca"\
          "&dt=rw&dt=rm&dt=ss&dt=t&ie=UTF-8&oe=UTF-8"\
          "&source=btn&ssel=3&tsel=3&kc=0&tk=%s&q=%s"%(tk,content)
    result = open_url(url)
    print_result(result)

def main():
    js = Return_tk()
    while True:
        print(termcolor.colored("请先输入要进行的操作：q表示退出；e表示英文翻译成中文；z表示中文翻译成英文。","red"))
        change = input("请选择翻译选项：")
        if change == 'q':
            break
        elif change == 'e':
            content = input("请输入要翻译的英文：")
            tk = js.getTk(content)
            en_to_zn_translate(content,tk)
        elif change ==  'z':
            content = input("请输入要翻译的中文：")
            tk = js.getTk(content)
            zn_to_en_translate(content,tk)
        else:
            print("请输入正确的选项！")

main()