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copied!<p>Reflection in python is a lot easier and far more flexible than it is in Java.</p> <p>I recommend reading this <a href="http://www.diveintopython.net/power_of_introspection/index.html" rel="noreferrer">tutorial</a></p> <p>There's no direct function (that I know of) which takes a fully qualified class name and returns the class, however you have all the pieces needed to build that, and you can connect them together.</p> <p>One bit of advice though: don't try to program in Java style when you're in python.</p> <p>If you can explain what is it that you're trying to do, maybe we can help you find a more pythonic way of doing it.</p> <p>Here's a function that does what you want:</p> <pre><code>def get_class( kls ): parts = kls.split('.') module = ".".join(parts[:-1]) m = __import__( module ) for comp in parts[1:]: m = getattr(m, comp) return m </code></pre> <p>You can use the return value of this function as if it were the class itself.</p> <p>Here's a usage example:</p> <pre><code>>>> D = get_class("datetime.datetime") >>> D <type 'datetime.datetime'> >>> D.now() datetime.datetime(2009, 1, 17, 2, 15, 58, 883000) >>> a = D( 2010, 4, 22 ) >>> a datetime.datetime(2010, 4, 22, 0, 0) >>> </code></pre> <p><strong>How does that work?</strong></p> <p>We're using <code>__import__</code> to import the module that holds the class, which required that we first extract the module name from the fully qualified name. Then we import the module:</p> <pre><code>m = __import__( module ) </code></pre> <p>In this case, <code>m</code> will only refer to the top level module, </p> <p>For example, if your class lives in <code>foo.baz</code> module, then <code>m</code> will be the module <code>foo</code><br> We can easily obtain a reference to <code>foo.baz</code> using <code>getattr( m, 'baz' )</code></p> <p>To get from the top level module to the class, have to recursively use <code>gettatr</code> on the parts of the class name</p> <p>Say for example, if you class name is <code>foo.baz.bar.Model</code> then we do this:</p> <pre><code>m = __import__( "foo.baz.bar" ) #m is package foo m = getattr( m, "baz" ) #m is package baz m = getattr( m, "bar" ) #m is module bar m = getattr( m, "Model" ) #m is class Model </code></pre> <p>This is what's happening in this loop:</p> <pre><code>for comp in parts[1:]: m = getattr(m, comp) </code></pre> <p>At the end of the loop, <code>m</code> will be a reference to the class. This means that <code>m</code> is actually the class itslef, you can do for instance:</p> <pre><code>a = m() #instantiate a new instance of the class b = m( arg1, arg2 ) # pass arguments to the constructor </code></pre>

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