"The Python Standard Library" page (https://docs.python.org/3.6/library/index.html#the-python-standard-library) has a link to "Python Package Index" in the fourth paragraph but it linked to 404 URI(https://pypi.org/pypi/). That link should be changed to a new URI(https://pypi.org/). --- Fourth paragraph "In addition to the standard library, there is a growing collection of several thousand components (from individual programs and modules to packages and entire application development frameworks), available from the ""Python Package Index""(This link is broken)."