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Python Python Collections (Retired) Dictionaries Teacher Stats

Laknath Gunathilake
Laknath Gunathilake
1,860 Points

difficulty passing stat challenge

when I run the following code

def stats(my_dict):
    stat=[]
    for teacher in my_dict:
        count=len(my_dict[teacher])
        stat.append(teacher+str(count))

I get something like
['Goerge1] where as what I need is ['Goerge','1']

```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(my_dict):
    max_teacher=''
    max_count=0
    for teacher in my_dict:
        count=len(my_dict[teacher])
        if count>max_count:
            max_teacher=teacher
            max_count=count
    return max_teacher 
def num_teachers(my_dict):
    return len(my_dict.keys())
def stats(my_dict):
    stat=[]
    for teacher in my_dict:
        count=len(my_dict[teacher])
        stat.append(teacher+str(count))

2 Answers

John Lindsey
John Lindsey
15,641 Points

It wants you to return a list of lists. So you will need to ".append([teacher, count])". This will append the list of the teacher name and class count to the list. Also it wants you to keep the count as an int rather than a string. Also, don't forget about the return statement(:

# 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.

# 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(my_dict):
    max_teacher=''
    max_count=0
    for teacher in my_dict:
        count=len(my_dict[teacher])
        if count>max_count:
            max_teacher=teacher
            max_count=count
    return max_teacher 
def num_teachers(my_dict):
    return len(my_dict.keys())
def stats(my_dict):
    stat=[]
    for teacher in my_dict.keys():
        count=len(my_dict[teacher])
        stat.append([teacher, count])
    return stat
Wairton Rebouças
Wairton Rebouças
8,225 Points

"Now, create a function named stats that takes the teacher dictionary. Return a list of lists in the format [<teacher name>, <number of classes>]. For example, one item in the list would be ['Dave McFarland', 1]."

you got ['Goerge1'] instead of ['Goerge','1'] because you're doing stat.append(teacher+str(count)), adding just one string with the two items concatenated instead of adding a list with two elements [teacher, count]. Note that you don't need to convert count to string and also remember of returning the 'stat' variable at the end of your function.