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Python Python Collections (Retired) Dictionaries Teacher Stats

Stuck on challenge 3 of teacher stats

Gettting the error: Didn't get the expected output.

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(dic):
  maiorclasse = 0
  professor = ""
  for prof in dic:
    if len(dic[prof]) > maiorclasse:
      maiorclasse = len(dic[prof])
      professor = prof
  return professor

def num_teachers(dic):
  n = len(dic.keys())

  return n

def stats(dic):
  lista = []
  for prof in dic:
    lista.append(prof)
    lista.append(len(dic[prof]))


  return lista

1 Answer

Steven Parker
Steven Parker
230,995 Points

When you add to your list:

    lista.append(prof)
    lista.append(len(dic[prof]))

...you are adding two items, first the name and then the number of classes. But the challenge is expecting your stats to return a list of items where each teacher's name and the number of classes are combined into one item.

You did have the right data items, so just combine them into one item and append that:

    lista.append([prof, len(dic[prof])])