Python program for reversing a string

First Method:

string = input("Enter a string:")

r = ""

l = len(string)

for a in range(l):

    r = r + string[l-a-1]

if(string == r):

    print(string, "is a palindrome")

else:

    print(string, "is not a palindrome")

Second Method: 

string = input("Enter a string:")

r = ""

length = len(string)

for a in range(-1, (-length-1), -1):

    r = r + string[a]

if(string == r):

    print(string, "is a palindrome")

else:

    print(string, "is not a palindrome")