Environments for python

A virtual environment is a Python tool for dependency management and project isolation. They allow Python site packages (third party libraries) to be installed locally in an isolated directory for a particular project, as opposed to being installed globally (i.e. as part of a system-wide Python).
Source

Adventages of using virtual environments

• Dependency issues: different package version for different projects.
• Installation without admin rights
• Keep a clean global site-packages folder
• Safely store credentials

Conda environments

@Mátyás

venv vs virtualenv

virtualenv

• Python2 and Python3
• Not standard library

venv

• Python3
• Standard library

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• Activate (PS, cmd, bash …)
• Deactivate
• Use the python path inside
• The python version used with which the environment is created

Requirement files

pip freeze > requirement.txt

Using git

Never commit the environment!
Commit the requirement.txt file!

Environmental variables

import os
from getpass import getpass

# Method1: get pw from user
pw = getpass("Enter password...")

# Method2: load from environmental variable
pw = os.getenv("MY_SECRET_PASSWORD")

Possible issues

• Copy-paste the project, including the “venv”
• where python or which python to see the interpreter path *