title: AttributeError: 'module' object has no attribute 'instrument'
body: <p>I have installed python 2.7, Pyvisa1.4 and ni-visa5.4 and get an error on running the following code.</p>
  
  <pre><code>import visa
  
  thermotron = visa.instrument("GPIB::30")
  </code></pre>
  
  <p>Error is </p>
  
  <pre><code>AttributeError: 'module' object has no attribute 'instrument'
  </code></pre>
  
  <p>how to solve this?</p>