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

Flatten a list

The third function named courses is the focus. I have tried out the code in workspaces and so far I can get a list of the courses without repeating any course already added. But I need to flatten the list. I have checked online but the explanations are not simple. I need to flatten the list to make a single list. Please help explain how this is done. Thank you.

teachers.py
# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.

def num_teachers(dict):
    new = dict
    number = len(new.keys())
    return (number)

def num_courses(dict):
    count = 0
    for teacher, courses in dict.items():
        if type(courses) is list:
            count += len(courses)
        else:
            count += 1
    return (count)  

def courses(dict):
    num = []
    for teacher, courses in dict.items():
        if courses in num:
            num.remove(courses)
        else:
            num.append(courses)
    return (num)

1 Answer

Andrey Misikhin
Andrey Misikhin
16,529 Points

You have the template from previous task, it is only need to add one cycle.

def courses(dict):
    num = []
    for teacher, courses in dict.items():
        if type(courses) is list:
            for course in courses:       
                num.append(course)
        else:
            num.append(courses)          
    return (num)