Use setup.cfg rather than setup.py.

A setup.cfg is cleaner, is easy to parse, and does not require running
any Python code. Its usage should be showcased.

Author: Steap

sample/__init__.py

@@ -1,3 +1,5 @@
+__version__ = '1.3.0'
+
 
 def main():
     """Entry point for the application script"""

setup.cfg

@@ -1,8 +1,189 @@
+# Arguments marked as "Required" below must be included for upload to PyPI.
+# Fields marked as "Optional" may be commented out.
+
 [metadata]
+# This is the name of your project. The first time you publish this
+# package, this name will be registered for you. It will determine how
+# users can install this project, e.g.:
+#
+# $ pip install sampleproject
+#
+# And where it will live on PyPI: https://pypi.org/project/sampleproject/
+#
+# There are some restrictions on what makes a valid project name
+# specification here:
+# https://packaging.python.org/specifications/core-metadata/#name
+# Required
+name = sampleproject
+
+# Versions should comply with PEP 440:
+# https://www.python.org/dev/peps/pep-0440/
+# You may also specify the version directly: version = 1.3.0
+version = attr:sample.__version__
+
+# This is a one-line description or tagline of what your project does. This
+# corresponds to the "Summary" metadata field:
+# https://packaging.python.org/specifications/core-metadata/#summary
+# Optional
+description = A sample Python project
+
+# This is an optional longer description of your project that represents
+# the body of text which users will see when they visit PyPI.
+#
+# Often, this is the same as your README, so you can just read it in from
+# that file directly (as we have already done above)
+#
+# This field corresponds to the "Description" metadata field:
+# https://packaging.python.org/specifications/core-metadata/#description-optional
+# Optional
+long_description = file: README.md
+
+# Denotes that our long_description is in Markdown; valid values are
+# text/plain, text/x-rst, and text/markdown
+#
+# Optional if long_description is written in reStructuredText (rst) but
+# required for plain-text or Markdown; if unspecified, "applications should
+# attempt to render [the long_description] as text/x-rst; charset=UTF-8 and
+# fall back to text/plain if it is not valid rst" (see link below)
+#
+# This field corresponds to the "Description-Content-Type" metadata field:
+# https://packaging.python.org/specifications/core-metadata/#description-content-type-optional
+# Optional (see note above)
+long_description_content_type = text/markdown
+
 # This includes the license file(s) in the wheel.
 # https://wheel.readthedocs.io/en/stable/user_guide.html#including-license-files-in-the-generated-wheel-file
 license_files = LICENSE.txt
 
+# This should be a valid link to your project's main homepage.
+#
+# This field corresponds to the "Home-Page" metadata field:
+# https://packaging.python.org/specifications/core-metadata/#home-page-optional
+# Optional
+url = https://github.com/pypa/sampleproject
+
+# This should be your name or the name of the organization which owns the
+# project.
+# Optional
+author = The Python Packaging Authority
+
+# This should be a valid email address corresponding to the author listed
+# above.
+# Optional
+author_email = [email protected]
+
+# Classifiers help users find your project by categorizing it.
+#
+# For a list of valid classifiers, see https://pypi.org/classifiers/
+classifiers =  # Optional
+    # How mature is this project? Common values are
+    #   3 - Alpha
+    #   4 - Beta
+    #   5 - Production/Stable
+    Development Status :: 3 - Alpha
+    # Indicate who your project is intended for
+    Intended Audience :: Developers
+    Topic :: Software Development :: Build Tools
+
+    # Pick your license as you wish
+    License :: OSI Approved :: MIT License
+
+    # Specify the Python versions you support here. In particular, ensure
+    # that you indicate whether you support Python 2, Python 3 or both.
+    # These classifiers are *not* checked by 'pip install'. See instead
+    # 'python_requires' below.
+    Programming Language :: Python :: 2
+    Programming Language :: Python :: 2.7
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.4
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+# This field adds keywords for your project which will appear on the
+# project page. What does your project relate to?
+# Optional
+keywords =
+    sample
+    setuptools
+    development
+
+# Specify which Python versions you support. In contrast to the
+# 'Programming Language' classifiers above, 'pip install' will check this
+# and refuse to install the project if the version does not match. If you
+# do not support Python 2, you can simplify this to '>=3.5' or similar, see
+# https://packaging.python.org/guides/distributing-packages-using-setuptools/#python-requires
+python_requires = >=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, <4
+
+# List additional URLs that are relevant to your project as a dict.
+#
+# This field corresponds to the "Project-URL" metadata fields:
+# https://packaging.python.org/specifications/core-metadata/#project-url-multiple-use
+#
+# Examples listed include a pattern for specifying where the package tracks
+# issues, where the source is hosted, where to say thanks to the package
+# maintainers, and where to support the project financially. The key is
+# what's used to render the link text on PyPI.
+# Optional
+project_urls =
+    Bug Reports = https://github.com/pypa/sampleproject/issues
+    Funding = https://donate.pypi.org
+    Say Thanks! = http://saythanks.io/to/example
+    Source = https://github.com/pypa/sampleproject/
+
+[options]
+packages = find:
+# This field lists other packages that your project depends on to run.
+# Any package you put here will be installed by pip when your project is
+# installed, so they must be valid existing projects.
+#
+# For an analysis of "install_requires" vs pip's requirements files see:
+# https://packaging.python.org/en/latest/requirements.html
+# Optional
+install_requires =
+    peppercorn
+
+[options.extras_require]
+# List additional groups of dependencies here (e.g. development
+# dependencies). Users will be able to install these using the "extras"
+# syntax, for example:
+#
+#   $ pip install sampleproject[dev]
+#
+# Similar to `install_requires` above, these must be valid existing
+# projects.
+dev =
+    check-manifest
+test =
+    coverage
+
+[options.entry_points]
+# To provide executable scripts, use entry points in preference to the
+# "scripts" keyword. Entry points provide cross-platform support and allow
+# `pip` to create the appropriate form of executable for the target
+# platform.
+#
+# For example, the following would provide a command called `sample` which
+# executes the function `main` from this package when invoked:
+console_scripts =
+    sample = sample:main
+
+# If there are data files included in your packages that need to be
+# installed, specify them here.
+#
+# If using Python 2.6 or earlier, then these have to be included in
+# MANIFEST.in as well.
+[options.package_data]
+    sample = package_data.dat
+
+[options.data_files]
+# Although 'package_data' is the preferred approach, in some case you may
+# need to place data files outside of your packages. See:
+# http://docs.python.org/3.4/distutils/setupscript.html#installing-additional-files
+#
+# In this case, 'data_file' will be installed into '<sys.prefix>/my_data'
+my_data = data/data_file
+
+
 [bdist_wheel]
 # This flag says to generate wheels that support both Python 2 and Python
 # 3. If your code will not run unchanged on both Python 2 and 3, you will