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Python Python Collections (Retired) Dictionaries Teacher Stats

Dhruv Ghulati
Dhruv Ghulati
1,582 Points
Posted by Dhruv Ghulati
Dhruv Ghulati
1,582 Points

Can't append key, len(value) to a list (append only takes one argument) - stuck with stats function

Hi , anyone know what's wrong with my code here? I tried append to add to a list one by one but that didn't work, now using list('string') to basically define what each item will be, but this isn't working. Not sure - do I need to define a new empty list of lists first?

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_count = 0
  teacher = ""
  for key, value in my_dict.items():
    if len(value) > max_count:
      teacher = key
      max_count = len(value)
  return teacher

def num_teachers(teacher_dict):
  return len(teacher_dict)

def stats(t_dict):
  statslist=list()
  for key,value in t_dict.items():
    statslist(key)=len(value)
  return statslist

1 Answer

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Lists don't have keys and, even if they did, you wouldn't use parentheses to access them, you'd use square brackets.

Dhruv Ghulati
Dhruv Ghulati
1,582 Points
Dhruv Ghulati
Dhruv Ghulati
1,582 Points

Thanks a lot Kenneth! Figured it out! Loving this.

def stats(t_dict):
  statslist=list()
  for key,value in t_dict.items():
    sublist=list()
    sublist.append(key)
    sublist.append(len(value))
    statslist.append(sublist)
  return statslist

I was having a problem as it was appending everything into the main list one by one (instead of forming a list of lists), then I figured out this sublist method for each iteration.