title: Do Cython extension types support class attributes?
body: <p>Python classes can have class attributes:</p>
  
  <pre><code>class Foo(object):
     bar = 4
  </code></pre>
  
  <p>Is there an analogous construct for defining class attributes in Cython extension types? For example, when I try to compile the following cython code</p>
  
  <pre><code>cdef class Foo:
      cdef int bar
      bar = 4
  </code></pre>
  
  <p>I get this error:</p>
  
  <pre><code>thing.c:773:3: error: use of undeclared identifier 'bar'
    bar = 4;
    ^
  1 error generated.
  error: command 'cc' failed with exit status 1
  </code></pre>