learning_python.md

path	title
/learnings/learning_python	Learning Python

Table Of Contents

• Pip
  • Properly configuring
• Using Python as a shell script replacement language

Pip

Now a days (Python 3.4+) Pip is built into Python.

python3 -m pip --version

Usually this is aliased to pip or pip3

Properly configuring

pip itself will tell you where your config files should be

pip3 config debug

This outputs

env_var:
env:
global:
  /Library/Application Support/pip/pip.conf, exists: False
site:
  /Applications/Xcode.app/Contents/Developer/Library/Frameworks/Python3.framework/Versions/3.8/pip.conf, exists: False
user:
  /Users/rwilcox/.pip/pip.conf, exists: False
  /Users/rwilcox/.config/pip/pip.conf, exists: False

When you do override a file correctly it will look like

env_var:
env:
global:
  /Library/Application Support/pip/pip.conf, exists: False
site:
  /Applications/Xcode.app/Contents/Developer/Library/Frameworks/Python3.framework/Versions/3.8/pip.conf, exists: False
user:
  /Users/rwilcox/.pip/pip.conf, exists: False
  /Users/rwilcox/.config/pip/pip.conf, exists: True
    some.setting.you.set.in.this.file: "value"
    another.setting.you.set: "another value"

Using Python as a shell script replacement language

Python has low level tools to handle this, deprecated tools to handle this, and high level tools to handle this. My favorite high level tool is currently subprocess.check_output.

import subprocess

res = subprocess.check_output("ls", shell=True, stderr=subprocess.STDOUT)
# res is a bytes object

output_as_lines = res.decode("utf-8").split("\n")

docs for subprocess.check_output.

It will throw a CalledProcessError if non-zero error code