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Python Python Collections (Retired) Dictionaries Teacher Stats

I don't get how I'm wrong (Code Challenge)

I'm on part 3 of the Code Challenge. When I enter my code as it is below, it says that "'str' object has no attribute 'append'".

I'm pretty sure it's pointing to the third to last line. However, I don't think item is a string, because I made sure that it was a list, as you can see in the last function, stats. How can I get the correct answer?

teachers.py
# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Often, it's a good idea to hold onto a max_count variable.
# Update it when you find a teacher with more classes than
# the current count. Better hold onto the teacher name somewhere
# too!
#
# Your code goes below here.
def most_classes(dict):
    max_count = 0
    max_teacher = None
    for key in dict:
        count = 0
        value = dict[key]
        for item in value:
            count += 1
            if count > max_count:
                max_count = count
                max_teacher = key
    return max_teacher
def num_teachers(dict):
    teacher_count = 0
    for key in dict:
        teacher_count += 1
    return teacher_count
def stats(dict):
    dict_list = []
    for key in dict:
        count = 0
        item = []
        item.append(key)
        for item in dict[key]:
            count += 1
        item.append(count)
        dict_list.append(item)
    return dict_list

you cant append count because its not an iterable your just increasing the value of count and still storing it in the count variable name.

def stats(teacher_dict):
    teachers  = []
    total = []
    result = []
    for k,v in teacher_dict.items():
        teachers.append(k)
        total.append(len(v))
    for t in teachers:
        result.append([t,total[teachers.index(t)]])
    return result

Oh okay. Thanks!

1 Answer

Steven Parker
Steven Parker
216,136 Points

You've already declared and assigned item when you get to this line:

        for item in dict[key]:

At that point it gets re-used to iterate through the strings of class names, ending up as one of the strings. But then you do this:

        item.append(count)

And that causes the error.

:point_right: You might want to pick a different variable name to iterate through the list of classes.

Thank you so much! I didn't realize that.