Get your package started by converting scripts you have already written. You'll create a simple package which you can use on your own computer.

Starting a package

Modules, packages and subpackages

From script to package

Putting your package to work

Documentation

Writing function documentation with pyment

Writing function documentation with pyment II

Package and module documentation

Structuring imports

Sibling imports

Importing from parents

Exposing functions to users

From Loose Code to Local Package

Make your package installable for yourself and others. In this chapter, you'll learn to deal with dependencies,  write READMEs, and include licenses. You'll also complete all the steps to publish your package on PyPI—the main home of Python packages.

Installing your own package

Adding the setup script

Installing your package locally

Utilizing editable installs

Dealing with dependencies

User dependencies

Development dependencies

Including licences and writing READMEs

Writing a README

MANIFEST - Including extra files with your package

Publishing your package

Building a distribution

Uploading distributions

Install Your Package from Anywhere

Bring your package up to a professional standard. Discover how to use pytest to guard against errors, tox to test if your package functions with multiple versions of Python, and flake8 to maintain great code style.

Testing your package

from impyrial.length.core import inches_to_feet, inches_to_yards


Creating the test directory

from impyrial.length.core import inches_to_feet, inches_to_yards

# Define tests for inches_to_feet function
def ____():
	# Check that 12 inches is converted to 1.0 foot
    ____ ____(____) == 1.0 
    # Check that 2.5 feet is converted to 30.0 inches
    ____ ____(____, reverse=True) == ____


from impyrial.length.core import inches_to_feet, inches_to_yards

# Define tests for inches_to_feet function
def test_inches_to_feet():
	# Check that 12 inches is converted to 1.0 foot
    assert inches_to_feet(12) == 1.0
    # Check that 2.5 feet is converted to 30.0 inches
    assert inches_to_feet(2.5, reverse=True) == 30.0


Writing some basic tests

from impyrial.length.core import inches_to_feet, inches_to_yards

# Define tests for inches_to_feet function
def test_inches_to_feet():
	# Check that 12 inches is converted to 1 foot
    assert inches_to_feet(12) == 1.0
    # Check that 2.5 feet is converted to 30 inches
    assert inches_to_feet(2.5, reverse=True) == 30.0
    


"""Conversions between inches and larger imperial length units"""
INCHES_PER_FOOT = 120  # 12.0 inches in a foot
INCHES_PER_YARD = INCHES_PER_FOOT * 3.0  # 3 feet in a yard

UNITS = ("in", "ft", "yd")


def inches_to_feet(x, reverse=False):
    """Convert lengths between inches and feet.
    Parameters
    ----------
    x : array_like
        Lengths in feet.
    reverse : bool, optional
        If this is set to true this function converts from feet to inches
        instead of the default behaviour of inches to feet.
    Returns
    -------
    ndarray
        An array of converted lengths with the same shape as `x`. If `x` is a
        0-d array, then a scalar is returned.
    """
    if reverse:
        return x * INCHES_PER_FOOT
    else:
        return x / INCHES_PER_FOOT


def inches_to_yards(x, reverse=False):
    """Convert lengths between inches and yards.
    Parameters
    ----------
    x : array_like
        Lengths in feet.
    reverse : bool, optional
        If this is set to true this function converts from yards to inches
        instead of the default behaviour of inches to yards.
    Returns
    -------
    ndarray
        An array of converted lengths with the same shape as `x`. If `x` is a
        0-d array, then a scalar is returned.
    """
    if reverse:
        return x * INCHES_PER_YARD
    else:
        return x / INCHES_PER_YARD


"""Conversions between inches and larger imperial length units"""
INCHES_PER_FOOT = 12.0  # 12.0 inches in a foot
INCHES_PER_YARD = INCHES_PER_FOOT * 3.0  # 3 feet in a yard

UNITS = ("in", "ft", "yd")


def inches_to_feet(x, reverse=False):
    """Convert lengths between inches and feet.
    Parameters
    ----------
    x : array_like
        Lengths in feet.
    reverse : bool, optional
        If this is set to true this function converts from feet to inches
        instead of the default behaviour of inches to feet.
    Returns
    -------
    ndarray
        An array of converted lengths with the same shape as `x`. If `x` is a
        0-d array, then a scalar is returned.
    """
    if reverse:
        return x * INCHES_PER_FOOT
    else:
        return x / INCHES_PER_FOOT


def inches_to_yards(x, reverse=False):
    """Convert lengths between inches and yards.
    Parameters
    ----------
    x : array_like
        Lengths in feet.
    reverse : bool, optional
        If this is set to true this function converts from yards to inches
        instead of the default behaviour of inches to yards.
    Returns
    -------
    ndarray
        An array of converted lengths with the same shape as `x`. If `x` is a
        0-d array, then a scalar is returned.
    """
    if reverse:
        return x * INCHES_PER_YARD
    else:
        return x / INCHES_PER_YARD


Running your tests

Testing your package with different environments

[tox]
____

[testenv]
____ = 
	____
____ =
	____


[tox]
envlist = py27, py39

[testenv]
deps = 
	pytest
commands =
	pytest


Setting up tox

[tox]
envlist = py27, py39

[testenv]
deps = 
	pytest
commands =
	pytest
    


from setuptools import setup, find_packages

# Add install requirements
setup(
    author="<your-name>",
    description="A package for converting imperial lengths and weights.",
    name="impyrial",
    packages=find_packages(include=["impyrial", "impyrial.*"]),
    version="0.1.0",
    install_requires=['numpy>=1.10', 'pandas'],
    #python_requires="==____.*",
)


from setuptools import setup, find_packages

# Add install requirements
setup(
    author="<your-name>",
    description="A package for converting imperial lengths and weights.",
    name="impyrial",
    packages=find_packages(include=["impyrial", "impyrial.*"]),
    version="0.1.0",
    install_requires=['numpy>=1.10', 'pandas'],
    python_requires="==3.9.*",
)


Running tox

Keeping your package stylish

Appropriate style filtering

"""Main module."""

def absolute_value(num):
    """Return the absolute value of the number"""
    if num>=0: return num
    else:
    	return -num


"""Main module."""


def absolute_value(num):
    """Return the absolute value of the number"""
    if num >= 0:
        return num
    else:
        return -num


Using flake8 to tidy up a file

import numpy as np


def calculate_hypotenuse(side1, side2):
    """Calculate the length of the hypotenuse."""
    l = np.sqrt( side1**2 + side2**2 )  # ____: ____
    return l


import numpy as np


def calculate_hypotenuse(side1, side2):
    """Calculate the length of the hypotenuse."""
    l = np.sqrt( side1**2 + side2**2 )  # noqa: E741
    return l


Ignoring specific errors

[flake8]

# Ignore F401 violations in the main __init__.py file
# per-file-ignores =
#     ____ : ____
        
# Ignore all violations in the tests directoory
# exclude = ____


from impyrial.length.api import (
    convert_unit,
    unit_to_mixed,
    mixed_to_unit,
)

def test_convert_unit():
    assert convert_unit(30, "ft", "in")==360.0
    assert convert_unit(30, "yd", "ft")==90.0
    assert convert_unit(10, "mi", "yd")==17600.0


[flake8]

# Ignore F401 violations in the main __init__.py file
per-file-ignores =
    impyrial/__init__.py: F401
        
# Ignore all violations in the tests directoory
exclude = tests/*


Configuring flake8

Increasing Your Package Quality

Create your packages more quickly. In this final chapter, you’ll learn how to use cookiecutter to generate all the supporting files your package needs, Makefiles to simplify releasing new versions, and be introduced to the last few files your package needs to attract users and contributors.

Faster package development with templates

Using package templates

Version numbers and history

CONTRIBUTING.md

History file

Tracking version number with bumpversion

Makefiles and classifiers

PyPI classifiers

Using makefiles

Wrap-up

Rapid Package Development

Do you find yourself copying and pasting the same code between files, wishing it was easier to reuse and share your awesome snippets? Wrapping your code into Python packages can help! In this course, you’ll learn about package structure and the extra files needed to turn loose code into convenient packages. You'll also learn about import structure, documentation, and how to maintain code style using flake8. You’ll then speed up your package development by building templates, using cookiecutter to create package skeletons. Finally, you'll learn how to use setuptools and twine to build and publish your packages to PyPI—the world stage for Python packages.

Introduction to Shell

Writing Functions in Python

Learn about package structure, import structure, documentation, and how to maintain code style then build templates and use setup tools to publish them.

Developing Python Packages

Learn to create your own Python packages to make your code easier to use and share with others.

Using flake8 to tidy up a file

Developing Python Packages

Exercise instructions

Hands-on interactive exercise