1) Write a function named "Countstr" that operates over a list which includes a series of strings. The function takes a string and outputs the number of occurrences of that string in the given list. For example: Assume that dlist is a list that the user wants to search for the number of occurrences for the string "synth". dlist ["synthetic","polymer","synthesizer", "abaqus", "python","synths","macro"] The function that you prepare will search for "synth" in each element of the list. The string synth has 3 occurrences in the list ["synthetic","polymer","synthesizer", "abaqus", "python", "synths","macro"]. Then it will report the number of occurrences as follows: The string synth has 3 occurrences in the list ["synthetic","polymer", "synthesizer", "abaqus", "python", "synths", "macro"].