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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Posted by Ashish Shah
Ashish Shah
1,468 Points

Why is this showing error? Please provide solution

Why is this showing error? Please provide solution

teachers.py 
def num_teachers(test2):
    return len(test2)
def num_courses(teachers):
    total = 0
    for value in teachers.values():
        # for the number of courses within that value
        for course in value:
            total += 1
    return total
def courses(teachers):
    output = []
    for courses in teachers.values():
        output +=courses


    return output


def num_courses(a_dict):
    a_list = []
    for key in a_dict:
        for item in key:
        if item not in a_list:
                 a_list.append(item)
        else:
                continue
            return a_list
def most_courses(teachers):
    all_courses = []
        for value in teachers.values():
    all_courses.extend(teachers)
        return all_courses