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copied!<p>There are a couple of options for how to proceed.</p> <p>The simplest might be to use nested dictionaries, so <code>Variable_FOO</code> becomes <code>config["variable"]["FOO"]</code>. You might want to use a <code>defaultdict(dict)</code> for the outer dictionary so you don't need to worry about initializing the inner ones when you add the first value to them.</p> <p>Another option would be to use tuple keys in a single dictionary. That is, <code>Variable_FOO</code> would become <code>config[("variable", "FOO")]</code>. This is easy to do with code, since you can simply assign to <code>config[tuple(some_string.split("_"))]</code>. Though, I suppose you could also just use the unsplit string as your key in this case.</p> <p>A final approach allows you to use the syntax you want (where <code>Variable_FOO</code> is accessed as <code>config.Variable["FOO"]</code>), by using <code>__getattr__</code> and a <code>defaultdict</code> behind the scenes:</p> <pre><code>from collections import defaultdict class Config(object): def __init__(self): self._attrdicts = defaultdict(dict) def __getattr__(self, name): return self._attrdicts[name] </code></pre> <p>You could extend this with behavior for <code>__setattr__</code> and <code>__delattr__</code> but it's probably not necessary. The only serious limitation to this approach (given the original version of the question), is that the attributes names (like <code>Variable</code>) must be legal Python identifiers. You can't use strings with leading numbers, Python keywords (like <code>global</code>) or strings containing whitespace characters.</p> <p>A downside to this approach is that it's a bit more difficult to use programatically (by, for instance, your config-file parser). To read a value of <code>Variable_FOO</code> and save it to <code>config.Variable["FOO"]</code> you'll probably need to use the global <code>getattr</code> function, like this:</p> <pre><code> name, value = line.split("=") prefix, suffix = name.split("_") getattr(config, prefix)[suffix] = value </code></pre>

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