Sum of Natural Numbers in Python

Write a Program in Python to find Sum of Natural Numbers.

DesiredNumber = int(input("Enter a DesiredNumberber: "))  
if DesiredNumber < 0:  
   print("Please Enter a positive DesiredNumberber")  
else:  
   sum = 0  
   # while loop to iterate again and again till zero  
   while(DesiredNumber > 0):  
       sum += DesiredNumber  
       DesiredNumber -= 1  
   print("The sum is",sum)

Output

Enter a DesiredNumberber: 8
The sum is 36

Exercise

Write a Program in Python to find Sum of odd Natural Numbers.