安装nltk的步骤(我已经在MAC OS X中安装了python3 (3.6.2)

sudo easy_install pip

使用ignore installed选项忽略卸载之前版本的6，否则，它会在卸载时给出一个错误，并且不进行电影转发

sudo pip3 install -U nltk --ignore-installed six

检查pip和python的安装，使用'3'版本

which python python2 python3
which pip pip2 pip3

检查NLTK是否安装

python3
import nltk
nltk.__path__
['/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/nltk']

在安装示例之前安装SSL证书，否则我们将在安装示例时证书错误

/Applications/Python\ 3.6/Install\ Certificates.command
python3 -m nltk.downloader book

这就成功地完成了nltk和nltk_ata的安装

The SSL: CERTIFICATE_VERIFY_FAILED error could also occur because an Intermediate Certificate is missing in the ca-certificates package on Linux. For example, in my case the intermediate certificate "DigiCert SHA2 Secure Server CA" was missing in the ca-certificates package even though the Firefox browser includes it. You can find out which certificate is missing by directly running the wget command on the URL causing this error. Then you can search for the corresponding link to the CRT file for this certificate from the official website (e.g. https://www.digicert.com/digicert-root-certificates.htm in my case) of the Certificate Authority. Now, to include the certificate that is missing in your case, you may run the below commands using your CRT file download link instead:

wget https://cacerts.digicert.com/DigiCertSHA2SecureServerCA.crt

mv DigiCertSHA2SecureServerCA.crt DigiCertSHA2SecureServerCA.der

openssl x509 -inform DER -outform PEM -in DigiCertSHA2SecureServerCA.der -out DigicertSHA2SecureServerCA.pem.crt

sudo mkdir /usr/share/ca-certificates/extra

sudo cp DigicertSHA2SecureServerCA.pem.crt /usr/share/ca-certificates/extra/

sudo dpkg-reconfigure ca-certificates

在此之后，您可以再次使用wget测试URL，也可以使用python urllib包进行测试。详情请参考:https://bugs.launchpad.net/ubuntu/+source/ca-certificates/+bug/1795242

我在Python 2.7.9中遇到了这个问题

以下是我所做的:

卸载Python 2.7.9 删除c:\Python27文件夹 下载了Python 2.7.18，这是今天最新发布的Python 2.7。 重新运行应用程序 它成功了!

不再有任何“[CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:581)”错误。

如果你在vCenter 6上，你应该将你vCenter的vmware证书颁发机构证书添加到你的操作系统的受信任CA列表中。要下载证书，请执行以下操作

打开Web浏览器。 导航到https:// 在右下角单击“下载受信任的根CA”链接

在Fedora

解压缩并将扩展名从.0更改为.cer 将其复制到/etc/pki/ca-trust/source/anchors/ 执行update-ca-trust命令。

链接:

https://virtualizationreview.com/articles/2015/04/02/install-root-self-signed-certificate-vcenter-6.aspx?m=1 http://forums.fedoraforum.org/showthread.php?t=293856

在Mac上安装证书解决了我的问题:

pip install certifi

如果你有私人证书要处理，比如你的组织自己的CA根和链的中间部分，那么最好将证书添加到CA文件中，即cacert。pem，而不是绕过整个安全设备(verify=False)。下面的代码让你在2.7+和3+

考虑添加整个证书链，当然您只需要这样做一次。

import certifi

cafile=certifi.where() # cacert file
with open ('rootca.pem','rb') as infile:
    customca=infile.read()
    with open(cafile,'ab') as outfile:
        outfile.write(customca)
with open ('interca.pem','rb') as infile:
    customca=infile.read()
    with open(cafile,'ab') as outfile:
        outfile.write(customca)
with open ('issueca.pem','rb') as infile:
    customca=infile.read()
    with open(cafile,'ab') as outfile:
        outfile.write(customca)

那这个应该能让你振作起来

import requests
response = requests.request("GET", 'https://yoursecuresite.com',  data = {})
print(response.text.encode('utf8'))

希望这能有所帮助