In Python to do sum up two strings, you have to convert the string value to an integer for calculating the addition of any other arithmetic operation.
Use int() function to convert a string to an integer.
Example Sum of two strings in Python
Simple example code calculates the sum of two given string numbers.
def sum_method(first, second):
return int(first) + int(second)
a = "100"
b = "200"
print(sum_method(a, b))
Output:

How do I sum two string inputs using Python?
Answer: Technically, you can’t perform a sum operation on a string input. However, you can join strings together to form a new string.
Simply store the two strings in a variable and combine them into a new variable.
string_1 = input("Enter first string: ")
string_2 = input("Enter second string: ")
res = string_1 + string_2
print(res)
Output:
Enter first string: Hello
Enter second string: Jo
HelloJo
Do comment if you have any doubts or suggestions on this Python string 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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