lazy load dictionary
<p>I have a dictionary called <code>fsdata</code> at module level (like a global variable). </p>

<p>The content gets read from the file system. It should load its data once on the first access. Up to now it loads the data during importing the module. This should be optimized. </p>

<p>If no code accesses <code>fsdata</code>, the content should not be read from the file system (save CPU/IO).</p>

<p>Loading should happen, if you check for the boolean value, too:</p>

<pre><code>if mymodule.fsdata:
    ... do_something()
</code></pre>

<p>Update: Some code already uses mymodule.fsdata. I don't want to change the other places. It should be variable, not a function. And "mymodule" needs to be a module, since it gets already used in a lot of code.</p>
