title: how to cycle module in python
body: <p>There are many modules in a folder named schema </p>
  
  <pre><code>schema
     demo.py
     demo1.py
     xxx.py
  </code></pre>
  
  <p>my code here</p>
  
  <pre><code>import schema
  for table in schema.__all__:
      do someting about table.xxx
  </code></pre>
  
  <p>I want to cyclic operate each module in schema, but table variable above code is a string, how can use the module with this table variable.</p>