title: Problems calling a Function - "not defined"
body: <p>as the topics asks: How do you import/reference another already written (exterior) program within a main program?</p>
  
  <p>if I have a file named Squares.py with this inside of it:</p>
  
  <pre><code>def squares(x):
       for i in x:
           return i*i
  squares(x) 
  </code></pre>
  
  <p>...how do I tell an umbrella program to reference it?  Do I use an import command at the top of the overhead program?  How would I write it?</p>