return “Please run pip from your system command prompt”

 

 

 

From: Python-ideas [mailto:python-ideas-bounces+tritium-list=sdamon.com@python.org] On Behalf Of Stephan Houben
Sent: Sunday, October 29, 2017 3:19 PM
To: Python-Ideas <python-ideas@python.org>
Subject: [Python-ideas] install pip packages from Python prompt

 

Hi all,

Here is in somewhat more detail my earlier proposal for

having in the interactive Python interpreter a `pip` function to

install packages from Pypi.

Motivation: it appears to me that there is a category of newbies

for which "open a shell and do `pip whatever`" is a bit too much.

It would, in my opinion, simplify things a bit if they could just

copy-and-paste some text into the Python interpreter and have

some packages from pip installed.

That would simplify instructions on how to install package xyz,

without going into the vagaries of how to open a shell on various

platforms, and how to get to the right pip executable.

I think this could be as simple as:

  def pip(args):
      import sys
      import subprocess
      subprocess.check_call([sys.executable, "-m", "pip"] + args.split())

      print("Please re-start Python now to use installed or upgraded packages.")

Note that I added the final message about restarting the interpreter

as a low-tech solution to the problem of packages being already

imported in the current Python session.

I would imagine that the author of package xyz would then put on

their webpage something like:

  To use, enter in your Python interpreter:

     pip("install xyz --user")

As another example, consider prof. Baldwin from Woolamaloo university

who teaches a course "Introductory Python programming for Sheep Shavers".

In his course material, he instructs his students to execute the

following line in their Python interpreter.

   pip("install woolamaloo-sheepshavers-goodies --user")

which will install a package which will in turn, as dependencies,

pull in a number of packages which are relevant for sheep shaving but

which have nevertheless irresponsibly been left outside the stdlib.

Stephan