Please use python and show test cases. and show test cases.

8.0 4. Function Two countLetter Specification The second function you will write should be called 'countLetter'. Your function should take two (2) arguments. The first will be a string. The second will be a single character. The function should return one (1) integer: the number of times the character occurs in the string. Hint: remember your string methods (see our book pp. 142-147) Testing: Create your own test cases. Think about what the edge cases are (e.g., what if the character is not in the string?)