title: Could not find information about 'NameError: date'
body: <p>I am working with pelican static site generator for my blog, I was using correctly, but strangely I found that <code>.md</code> articles are not compiling and it throws me these strange errors.</p>
  
  <p>I looked at my article pages, everything is fine, this is my article header</p>
  
  <pre><code>Title: some title
  slug: some-title
  Date: 2016-11-19
  Category: code
  Tags: python, python
  Authors: nix1947(Manoj)
  </code></pre>
  
  <p>I couldn't find, why I am getting this error?</p>
  
  <p>I looked over the  <code>pelicanconf.py</code> file, particularly for the date section, everything is ok
  here is my date section of my pelicanconf.py file</p>
  
  <pre><code>DATE_FORMAT = { 'en': '%d %m %Y'}
  DEFAULT_DATE_FORMAT = '%d %m %Y'
  PDF_GENERATOR = False
  REVERSE_CATEGORY_ORDER = True
  ARTICLE_URL = '{date:%Y}/{date:%-m}/{date:%-d}/{slug}/'
  ARTICLE_SAVE_AS = ARTICLE_URL + 'index.html'
  </code></pre>
  
  <p>These are the bunch of errors that pelican throws when I try to compile an article.</p>
  
  <pre><code>(nix1947blog)nix1947@nix1947:~/projects/nix1947blog/content/blog$ 
  -&gt; Modified: content. re-generating...
  ERROR: Skipping blog/output/tags.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/categories.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/archives.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/Updating-linux-packages-from-particular-repositories.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/heroku-rails-cheatsheet.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/Data structures and algorithms using python.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/rails-5-cheatsheet.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/authors.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/index.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/Web-scraping-using-python-3.5.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/hello-world.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/installing-latex-in-linux.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/author/nix1947.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/author/nix1947manoj-gautam.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/category/sysadmin.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/category/code.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/category/documentation.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/ruby.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/linux.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/python.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/programming.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/documentation.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/system-admininstration.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/rails.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/publishing.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/blog.html: could not find information about 'NameError: date'
  ERROR: Skipping blog/output/tag/heroku.html: could not find information about 'NameError: date'
  Done: Processed 6 articles, 0 drafts, 0 pages and 0 hidden pages in 0.32 seconds.
  </code></pre>