How to use the extinction.__version__ function in extinction

# The master toctree document.
master_doc = 'index'

# General information about the project.
project = u'extinction'
copyright = u'2016, Kyle Barbary and contributors'

# The version info for the project you're documenting, acts as replacement for
# |version| and |release|, also used in various other places throughout the
# built documents.
#
# THe short X.Y version.
version = '.'.join(extinction.__version__.split('.')[0:2])

# The full version, including alpha/beta/rc tags.
release = extinction.__version__

# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
exclude_patterns = ['_build']

# The reST default role (used for this markup: `text`) to use for all
# documents.
default_role = 'obj'

# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'sphinx'


# -- Options for HTML output ----------------------------------------------

# The theme to use for HTML and HTML Help pages.  See the documentation for