pip 安装包包错，网站不信任，需要验证。
报错：

WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: certificate is not yet valid (_ssl.c:1056)'))': /simple/decord/

解决方法：

先查看系统时间，如果系统时间错误，先通过更改正确的系统时间。如果仍然报错，可以尝试以下操作：
添加信任站点
 

pip install -r requirements.txt --trusted-host pypi.org  

-------------------------------------------------------
 Could not fetch URL https://pypi.org/simple/flask/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/flask/ (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1056)'))) - skipping