What does it mean "weakly-referenced object no longer exists"?
<p>I am running a Python code and I get the following error message:</p>

<pre><code>Exception exceptions.ReferenceError: 'weakly-referenced object no longer exists' in &lt;bound method crawler.__del__ of &lt;searchengine.crawler instance at 0x2b8c1f99ef80&gt;&gt; ignored
</code></pre>

<p>Does anybody know what can it means?</p>

<p>P.S.
This is the code which produce the error:</p>

<pre><code>import sqlite

class crawler:

  def __init__(self,dbname):
    tmp = sqlite.connect(dbname)
    self.con = tmp.cursor()

  def __del__(self):
    self.con.close()

crawler =  crawler('searchindex.db')
</code></pre>
