小编but*_*ife的帖子

我正在尝试执行以下操作：

from urllib.request import urlopen
data = urlopen("https://www.duolingo.com/users/SaifullahS6").read()

我收到以下错误：

URLError: <urlopen error [WinError 10060] A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond>

同样，当我尝试这样做时：

import requests
session = requests.Session()
data = {"login": "SaifullahS6", "password": "mypassword"}
req = requests.Request('POST', "https://www.duolingo.com/login", data=data,         
cookies=session.cookies)
prepped=req.prepare()
returned = session.send(prepped)

我得到：

ConnectionError: HTTPSConnectionPool(host='www.duolingo.com', port=443): Max retries exceeded with url: /login (Caused by NewConnectionError('<requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x000000000E6948D0>: …

我有以下来自在线 C++ 课程的代码：

class tempStat
{
    public:
    // Data members.
    double minimum, maximum;

    // Constructor.
    tempStat(double min = 0.0, double max = 0.0)
        : minimum(min), maximum(max)
    {}

    // Helper method, to write a tempStat object to a file in binary format.
    void write(std::ostream & os)
    {
        os.write((char*)&minimum, sizeof(double));
        os.write((char*)&maximum, sizeof(double));
    }

    // Helper method, to read a tempStat object from a file in binary format.
    void read(std::istream & is)
    {
        is.read((char*)&minimum, sizeof(double));
        is.read((char*)&maximum, sizeof(double));
    }
}

这个类是这样使用的：

tempStat ts;
ts.read(ifile); …

我看过在线课程，他们有如下示例：

from itertools import count
  
# creates a count iterator object
iterator =(count(start = 0, step = 2))
  
# prints an even list of integers
print("Even list:", 
      list(next(iterator) for _ in range(5)))

...您可以使用range或 来编写np.arange。这是另一个例子：

# list containing some strings
my_list =["x", "y", "z"]
  
# count spits out integers for 
# each value in my list
for i in zip(count(start = 1, step = 1), my_list):
    print(i)

...这基本上只是enumerate。所以我的问题是：您能否举一个使用 无法完成（或必须更加笨拙地完成）的itertools.count示例？itertools.islicerange