You have a list of students' names and their grades (in exams taken in PTSL course) in the form of word-colon- number (1.e. 'Student_name:Grade'). You need to complete the following Python function which will find the sum of all grades of each student and will return a dictionary where the key is the student name and its value is the total sum For example, if the list is: L'Ahmad:15', 'All 20', 'Sara:16', 'Ahmad:12', 'A:30) The function will return the following dictionary: {'Ahmad': 27. 'All':50, 'Sara': 16 def checkStudentsum(std_list): 2 A B = =