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Welcome to Click

.. image:: _static/click-name.svg :align: center :height: 200px

Click is a Python package for creating beautiful command line interfaces in a composable way with as little code as necessary. It's the "Command Line Interface Creation Kit". It's highly configurable but comes with sensible defaults out of the box.

It aims to make the process of writing command line tools quick and fun while also preventing any frustration caused by the inability to implement an intended CLI API.

Click in three points:

arbitrary nesting of commands
automatic help page generation
supports lazy loading of subcommands at runtime

What does it look like? Here is an example of a simple Click program:

.. click:example::

import click

@click.command()
@click.option('--count', default=1, help='Number of greetings.')
@click.option('--name', prompt='Your name',
              help='The person to greet.')
def hello(count, name):
    """Simple program that greets NAME for a total of COUNT times."""
    for x in range(count):
        click.echo(f"Hello {name}!")

if __name__ == '__main__':
    hello()

And what it looks like when run:

.. click:run::

invoke(hello, ['--count=3'], prog_name='python hello.py', input='John\n')

It automatically generates nicely formatted help pages:

.. click:run::

invoke(hello, ['--help'], prog_name='python hello.py')

You can get the library directly from PyPI::

pip install click

Documentation

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faqs

Tutorials

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quickstart virtualenv

How to Guides

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entry-points setuptools standalone-apps upgrade-guides support-multiple-versions

Conceptual Guides

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design-opinions why click-concepts

General Reference

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parameters parameter-types options option-decorators arguments commands-and-groups commands documentation prompts handling-files advanced complex extending-click testing utils shell-completion exceptions command-line-reference unicode-support wincmd

API Reference

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api

About Project

This documentation is structured according to Diataxis <https://diataxis.fr/>_ and written with MyST <https://myst-parser.readthedocs.io/en/latest/>_
Version Policy <https://palletsprojects.com/versions>_
Donate <https://palletsprojects.com/donate>_

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contributing contrib license changes