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Python Python Collections (Retired) Dictionaries Teacher Stats

reza sajadian
reza sajadian
718 Points

Hi. I have a dictionary of teachers which I need to extract the teacher who has taught the most courses.

Here is my code:

# 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.

teacher_dict = [
  {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
   'Kenneth Love': ['Python Basics', 'Python Collections']}
]
def most_classes(teacher_dict):
  new_dict1 = {}
  new_dict2 = {}
  for key in teacher_dict:
    temp_item = key
    item_count = len(teacher_dict[key].values())
    new_dict1 = dict{['temp_item' = item_count]  #I've tried to create a new dictionary which contains the keys and the number of courses every key has taught.
               }
    new_dict2.append(new_dict1) 
    pref = new_dict2.keys(max(new_dict2.values())) #Here I tended to extract the key in which contains the biggest number as value
    return(pref)
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.

[MOD: added ```python formatting -cf]

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points

The solution is to walk through the items in the dictionary and compare the length of each teachers courses to the "current max", if it's larger, set this teacher as the current max. The code will need to initialize the current max to 0 and the teacher to "no one" (empty string, or some other). At the end of the loop, return the maximum results.

# Task 1 of 4
# Create a function named 'most_classes' that takes a dictionary
# of teachers and returns the teacher with the most classes.
def most_classes(dct):
    count = 0
    teacher = ""
    for item in dct:
        classes = len(dct[item])
        if classes > count:
            count = classes
            teacher = item
    return teacher