How to call function inside "if" statement?

I am trying to find the longest palindrome in a given string. I came across a strange behavior of if statement. posting both the codes here, in 1st code when I tried debugging everything is working fine till if statement, but even after getting True, it is not accessing the further code inside.

Whereas in the second code I stored the return value of palindrome function in the boolean var and then used it in if statement. now it is accessing the inside code.

I guess I am missing something very fundamental in python. Please can someone tell why is this happening?

Code 1:

def palindrom(temp):
    if(temp==temp[::-1]):
        return True
    else:
        return False

word=input("enter the string to check  ")
maxx=""                                    #to store the longest palindrome till now
l=len(word)
for i in range(0,l):
    # if(len(maxx)>l-i):                   ## to check if remaining string is smaller than maxx
    #     print(maxx)
    #     break
    temp=word[i]                           ## testing by adding one letter at a time
    for j in range(i+1,l):
        temp=temp+word[j]
        if(temp is palindrom(temp)  and  len(temp)>len(maxx) ):
            maxx=temp                      ##updating the maxx
print(maxx)

Code 2:

def palindrom(temp):
    if(temp==temp[::-1]):
        return True
    else:
        return False

word=input("enter the string to check  ")
maxx=""
l=len(word)
for i in range(0,l):
    # if(len(maxx)>l-i):  ## to check if remaining string is smaller than maxx
    #     print(maxx)
    #     break
    temp=word[i]
    for j in range(i+1,l):
        temp=temp+word[j]
        bul=palindrom(temp)  ##storting the return value of palindrome() in a boolean.
        if(bul and  len(temp)>len(maxx)):
            maxx=temp
print(maxx)