Python：pip install不适用于任何软件包

Question

我目前正在使用MacOS（10.13.4）和Python 2.7.14。

我根本无法安装pip来安装任何软件包。我得到的是以下错误

    Collecting scrapy
  Could not fetch URL https://pypi.python.org/simple/scrapy/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:661) - skipping
  Could not find a version that satisfies the requirement scrapy (from versions: )
No matching distribution found for scrapy

仅供参考，这是另一个包错误消息：

Collecting dateutil
  Could not fetch URL https://pypi.python.org/simple/dateutil/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:661) - skipping
  Could not find a version that satisfies the requirement dateutil (from versions: )
No matching distribution found for dateutil

不确定这是否相关，但也是如此：

$ which openssl
/usr/bin/openssl

$ openssl version
LibreSSL 2.2.7

来自Python：

>>> import ssl
>>> print ssl.OPENSSL_VERSION
OpenSSL 0.9.8zh 14 Jan 2016

在这一点上的任何帮助将不胜感激。