setup(**config); rookie

Mon May 28 09:20:06 EDT 2012

I going thru a 101 and came upon this (http://
learnpythonthehardway.org/book/ex46.html)
try:
 from setuptools import setup
except ImportError:
 from distutils.core import setup
config = {
 'description': 'My Project',
 'author': 'My Name',
 'url': 'URL to get it at.',
 'download_url': 'Where to download it.',
 'author_email': 'My email.',
 'version': '0.1',
 'install_requires': ['nose'],
 'packages': ['NAME'],
 'scripts': [],
 'name': 'projectname'
}
setup(**config)
What is the construct **?
Thank you