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Python Python Collections (Retired) Dictionaries Teacher Stats

python unhashable type list means what ??

I think i missed something, but i can not see that. so help me please

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(a):
  kkey = ""
  maxc = 0
  for i in a:
    if len(a[i]) > maxc:
      maxc = len(a[i])
  for i in a:
    if len(a[i]) == maxc:
      return i
def num_teachers(a):
  tnt = 0
  tea = []
  for i in a:
    if i not in tea:
      tea.append(i)
      tnt += 1
  return tnt

def stats(a):
  dd = {}
  for i in a:
    dd[i] = len(a[i])
  return dd

1 Answer

Your only issue is that you have dd as a dictionary when it is expecting a list of lists.

def stats(a):
    dd = []
    for i in a:
        dd.append([i, len(a[i])])
    return dd