How do I return key based on a value?

Question

My most_courses function isn't passing, but it works in my own module.

What's up with that?

Thanks.

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(treeDict):
    return len(treeDict.keys())

def num_courses(treeDict):
    count = 0
    for v in treeDict.values():
        count += len(v)
    return count

def courses(treeDict):
    courseList = []
    for v in treeDict.values():
        for course in v:
            courseList.append(course)
    return((courseList))

def most_courses(treeDict):
    theBigOne = max(len(value) for value in treeDict.values())
    teachers = []
    for key, value in treeDict.items():
        if len(value) == theBigOne:
            teachers.append(key)
    return teachers

Answer 1 · 2017-09-20T00:51:59Z

September 20, 2017 12:51am

The challenge expects the method to return a single name, not a list of names. So it is expecting a string in return, not a list. If you convert your list to a string like this:

def most_courses(treeDict):
    theBigOne = max(len(value) for value in treeDict.values())
    teachers = []
    for key, value in treeDict.items():
        if len(value) == theBigOne:
            teachers.append(key)
    return ''.join(teachers)

Or not make it a list in the first place like this:

def most_courses(treeDict):
    theBigOne = max(len(value) for value in treeDict.values())
    teacher = ''
    for key, value in treeDict.items():
        if len(value) == theBigOne:
            teacher = key
    return teacher

Then your code will be accepted.

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Gabriel Corso

Gabriel Corso

How do I return key based on a value?

1 Answer

andren

andren