I am a Python noob, can you help me fix my syntax errors? : <p>This is a food timer for pizza, readymeals and curry. The interpreter returns a bunch of syntax errors. Could someone help me clean up the code? I'd be grateful.</p>

<pre><code>import os # Native commands
import time #Timer
import sys

choice = "" # Defining
p = "pizza" # Defining 
r = "readymeal" # Defining 
c = "curry" # Defining 

class Main:
# Check something = True/False
def UserInput():
    try:
        choice = raw_input("Which food?")
        if choice != p or r or c:
            print "Invalid choice"
            exit()                      

if choice == p:
    print "Alarm Set"
    time.sleep(900) # 15 Min
    os.system("start Alien_Siren.mp3") # Notification
elif choice == r:
    print "Alarm Set"
    time.sleep(420) # 7 Min
    os.system("start Alien_Siren.mp3") # Notification
elif choice == c:
    print "Alarm Set"
    time.sleep(420)
elif choice == "pizza and" and "readymeal": # Must type pizza and readymeal
    print "Alarm Set"
    time.sleep(1320) # 22 Min
elif choice == "exit": # Exit
    exit()
</code></pre>
