title: Pyusb on Windows 7 cannot find any devices
body: <p>So I installed Pyusb 1.0.0-alpha-1<br>
  Under Windows, I cannot get any handles to usb devices.</p>
  
  <pre><code>&gt;&gt;&gt; import usb.core
  &gt;&gt;&gt; print usb.core.find()
  None
  </code></pre>
  
  <p>I do have 1 usb device plugged in(idVendor=0x04d8, idProduct=0x0042), and I tried <code>usb.core.find(idVendor=0x04d8, idProduct=0x0042)</code> but that failed too.</p>
  
  <p>Under Ubuntu, with the same versions of pyusb and python (2.6), I am able to successfully find my device with that code, and communicate with it.</p>
  
  <p>So how can I get pyusb to find usb devices on Windows 7?</p>