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Python Python Collections (Retired) Dictionaries Teacher Stats

Craig Campbell
Craig Campbell
14,428 Points

can't seem to get the list of lists correct....

I could get it to make a list of lists like this: [ [name 1, name2, ...] , [number of classes 1, number of 2, ....]

But I couldn't get it to do [ [ name 1, class 1] , [name 2, classes 2], ...]

Can someone check my code? I need a hint here...

stats(teacher_dict)

teachers.py
#!/usr/bin/env python3
'''
Create a function named most_classes that takes a dictionary of teachers
and returns the teacher with the most classes.
'''
# 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(dictionary):
  max_count = 0
  most_teacher = ""
  for key in dictionary:
   if len(dictionary[key]) > max_count:
    max_count = len(dictionary[key])
    most_teacher = key

  return most_teacher


'''
Create a function named num_teachers that takes a dictionary of teachers
and returns the number of teachers.
'''

def num_teachers(dictionary):
  teacher_count = 0
  for teachers in dictionary:
    teacher_count = teacher_count + 1

  return teacher_count




''' create a function named stats that takes a dictionary of teachers and
returns a list of lists in the format [<name>, <number of classes>]
'''


def stats(dictionary):
  name_list = []
  class_count_list = []
  final_list = []

  for name in dictionary:
    name_list.append(name)
    class_count_list.append(len(dictionary[name]))



  final_list.append(name_list)
  final_list.append(class_count_list)


  return final_list


# I could get it to make a list of lists like this:  [ [name 1, name2, ...] , [number of classes 1, number of  2, ....]
# But I couldn't get it to do [ [ name 1, class 1] , [name 2, classes 2], ...]


# Can someone check my code?  I need a hint  here...
# stats(teacher_dict)

2 Answers

Hanley Chan
Hanley Chan
27,771 Points

Hi,

For your final list you ended up with what you got because you are appending your class_count_list to the end of your name_list.

Here is how I solved this one. I changed the for loop to append [name, #classes] to final_list

 for name in dictionary:
    final_list.append([name, len(dictionary[name])]) 

return final_list
Craig Campbell
Craig Campbell
14,428 Points

wow. Thanks, Hanley! That was an amazingly simple fix! Gracias!