please use python and check test cases

3. Function One: checkSum Specification The first function you will write should be called 'checkSum'. Your function should take one (1) argument: a string. The function should return one (1) integer: the checksum. A checksum is a single number that can act as a kind of "digital signature" of a long string. Just ike how two people will have different handwritten signatures, two strings can have two different digital signatures. There are many ways to calculate the checksum of any arbitrary string; the more complex the calculation, the less likely it is for two strings to have the same checksum value. You will calculate the checksum according to the following algorithm. First, sum the Unicode values of each character in the string. Second, take the sum modulo 10. This will be the checksum of the string. Page 2 of 4 CS 105 Intro to Computing Non-Tech Spring 2018 The ord ) function, when given a single character, returns the Unicode value of that character. (Hint: do not pass the entire string to the ord () function, it will not do what you want.) Example Test Case checkSum ('cat') returns