You have to take n number input from the user or provide a default value of to sum of n numbers in Python using for loop.
Example sum of n numbers in Python using for loop
Simple example code finds Sum of N Natural Numbers using While Loop, For Loop, and Functions.
Using For Loop
This program allows users to enter any integer value. After the user input number calculates the sum of natural numbers from 1 to user-specified value using For Loop.
number = int(input("Enter any Number: "))
total = 0
for value in range(1, number + 1):
total = total + value
print("The Sum of Natural Numbers = {1}".format(number, total))
Output:

Using While Loop
number = int(input("Enter any Number: "))
total = 0
value = 1
while value <= number:
total = total + value
value = value + 1
print("The Sum of Natural Numbers = {1}".format(number, total))
Output:
Enter any Number: 4
The Sum of Natural Numbers = 10
Using Functions
def sum_n(num):
if num == 0:
return num
else:
return num * (num + 1) / 2
number = int(input("Number: "))
total = sum_n(number)
print(total)
Output:
Number: 2
3.0
Do comment if you have any doubts or suggestions on this Python sum topic.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.

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