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copied!<p>I restructured your example a little to better illustrate the variants I'll use to explain the behaviour</p> <h3><a href="http://ideone.com/TWdgk" rel="nofollow">With temporary variables</a></h3> <pre><code>import inspect def print_id(obj): print "{} => {}".format(id(obj), obj) def getmember(obj, name): #members = dict(inspect.getmembers(obj)) #return members[name] return [member for _name, member in inspect.getmembers(obj) if name == _name][0] class Foo(object): def bar(self): pass foo = Foo() m1 = foo.bar m2 = getattr(foo, 'bar') m3 = getmember(foo, 'bar') print_id(m1) print_id(m2) print_id(m3) </code></pre> <p>However, if you inspect objects in a REPL, the basic structure of your code will probably look like this:</p> <h3><a href="http://ideone.com/eGr5T" rel="nofollow">Without temporary variables</a></h3> <pre><code>#... foo = Foo() print_id(foo.bar) print_id(getattr(foo, 'bar')) print_id(getmember(foo, 'bar')) </code></pre> <p>The <code>id()</code> function basically returns the memory address of an object. That is, it's not an identity that's unique between all objects created during the whole runtime of a program. It's only unique between all the objects that exist in the process at any given point in time.</p> <p>The explanation that fits the difference between the two examples is that resolving <code>foo.bar</code> in any of the three ways gives you <strong>a new object every time</strong>. In the first example, these objects are stored in temporary variables, so all three have to be located at different memory addresses.</p> <p>In the second example, the bound method object is no longer needed after it's printed out; the Python reference counting GC will free its memory. This means that the next time the bound method object is created, it's a new object that happens to get created at the same memory address as the previous one. This is why it can seem like you're getting the same object multiple times.</p> <p>That you always get a new bound method object can be shown trivially:</p> <pre><code>>>> foo.bar == foo.bar True >>> foo.bar is foo.bar False </code></pre>

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