How do I terminate a program in Python?
<p>This is my project description:</p>

<p>Write a program that displays the following menu:</p>

<blockquote>
  <p>1) Convert Fahrenheit to Celsius<br>
  2) Convert Celsius to Fahrenheit  </p>
  
  <p>Enter 1, 2, or 0 to exit: </p>
</blockquote>

<p>In the case of options 1 and 2, the program should then prompt the user for the temperature, perform the conversion, and output the result. Then the program should re-display the menu. When option 0 is chosen, the program should exit.</p>

<p>Here is what I have so far:</p>

<pre><code>a = raw_input("1) Convert Fahrenheit to Celsius \n2) Convert Celsius to Fahrenheit \nEnter 1, 2, or 0 to exit: ")

x = raw_input("Enter degree: ")

y = float((x - 32) / 1.8)

x = raw_input("Enter degree: ")

z = float((x + 32) * 1.8)

if a == 1:
    print(y)

if a == 2:
    print(z)
</code></pre>

<p>How can I terminate this program? Where else am I messing up?</p>
