All things Python
flake8
-
Usage:
To skip file enter this comment in that file, preferably at the top.
# flake8: noqa
To not issue warnings, add the following comment at the end of the file.
# noqa # or # noqa: <error-token> # or # noqa: <error-token>, <error-token>...
-
VS Code
"python.linting.flake8Enabled": true, "python.linting.pylintEnabled": false, "python.linting.flake8Args": [ "--max-line-length=200", "--ignore=D,E111,E127,E128,E225,E501,E731,E731,E901,F403,F405,W291,W293,W391" ],
PySnooper
- Usage:
import pysnooper @pysnooper.snoop()
Installing packages
There are differences in installing packages in the two versions of Python
For python version 2:
python -m pip install pyfirebase
or if you updated the shell command:
python2 -m pip install pyfirebase
For python version 3:
pip install pyfirebase
Different versions of Python
Using pyenv
brew install pyenv
pyenv install <version>
. For the full list, run pyenv install --list
Always use virtual environments
Virtualenv
For a specific directory set python version: pyenv local <version>
mkvirtualenv --python=$(pyenv which python) <env name>
Then use workon
(that comes with virtualenv-wrapper)
Download & install
Steps:
- Download from the Python website and install.
- Add to Path
- Click on
Add to Path
in the installation windows, otherwise: - Navigate to My Computer (System)/ Properties/ Advanced Settings/ Environment Variables and add
c:\Python36\
PIP (package installer for Python)
Python3 comes with pip installed.
Python 2 (deprecated)
`python2` and `python3` shall be used to specify Python version 2 and Python version 3 respectively.- Do Step 1
Add to Path
-
Click on
Add to Path
in the installation windows, otherwise: -
Navigate to My Computer (System)/ Properties/ Advanced Settings/ Environment Variables and add
c:\Python27\
(for Python2) and/orc:\Python36\
(for Python3)
Update shell command to call python
If you are one version of Python skip this part. Otherwise, I would advise to update the less used python version as described below:
For:
python2
- Navigate to the Python27 folder in C:\ and change python.exe to python2.exe.
python3
- Navigate to the Python32-36 (or otherwise) folder in C:\ and change python.exe to python3.exe
PIP (package installer for Python)
Python3 comes with pip installed.
Install pip in python2
python get-pip.py
or if you updated the shell command:
python2 get-pip.py
Installing packages
Virtual Environments in Windows
Virtual environments
More details are here featuring the three main ways to create and use virtual environments in Python:
- pipenv
- virtualenv
- virtualenv-wrapper
and bonus:
- venv (Avaliable in python 3.3+)
pipenv
# First install pipenv package:
<pip install pipenv>
cd project_folder
pipenv install <package>
pipenv run <script>
pipenv shell # Shell (Anthing run after this is done within the environment)
venv (Avaliable in python 3.3+)
python3 -m venv /path/to/new/virtual/environment
virtualenv
# First install virtualenv package:
<pip install virtualenv>
cd project_folder
# Create environment
virtualenv <environment-name>
# or
virtualenv </path/to/new/virtual/environment>
# Specify python version for the environment
virtualenv -p <python-version shell-command> <environment-name>
# or
virtualenv -p <python-version shell-command> </path/to/new/virtual/environment>
# Activate environment
source <environment-name>/bin/activate
# or
source </path/to/new/virtual/environment>/bin/activate
<pip install package>
deactivate
virtualenv-wrapper
# First install virtualenvwrapper package:
<pip install virtualenvwrapper>
export WORKON_HOME=~/Envs
source /usr/local/bin/virtualenvwrapper.sh
# or
source <path/to/virtualenvwrapper.sh>
mkvirtualenv <environment-name>
workon <environment-name>
deactivate
workon <previously-created-environment-name>
mkvirtualenv <previously-created-environment-name>
virtualenvwrapper-win
For Windows the package is virtualenvwrapper-win
and WORKON_HOME is %USERPROFILE%\Envs
by default.
This comment has been minimized.
Thank you, I had a bit of difficulty using VSC.