"""prgm"""
def add(att1, att2):
    """prgm"""
    sum = int(att1) + int(att2)
    if sum == 0:
        return sum 
    elif att1.isdigit and att2.isdigit:
        return sum
    else:
        return False

# take input from the user
print "Addition of two numbers"

#A = raw_input("Enter first number: ")
#B = raw_input("Enter second number: ")
A = '45'
B = '56'
print A, "+", B, "=", add(A, B)

@@ -44,19 +44,19 @@
 %22%22%22%0A    
-sum
+ans
  = int(a
@@ -79,19 +79,19 @@
 %0A    if 
-sum
+ans
  == 0:%0A 
@@ -104,19 +104,19 @@
  return 
-sum
+ans
  %0A    el
@@ -168,11 +168,11 @@
 urn 
-sum
+ans
 %0A   

Create addition.py