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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Posted by Maiia Spivak
Maiia Spivak
3,038 Points

stats function - list of lists in Python

Please take a look at my script. I am getting more and more confused with this challenge...

teachers.py 
# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.
def num_teachers(teacher_dict):
    return len(teacher_dict)

def num_courses(teacher_dict):
    count = 0
    for arr in teacher_dict.values():
        for item in arr:
            count += 1
    return count

def courses(teacher_dict):
    courses = []
    for arr in teacher_dict.values():
        for item in arr:
            courses.append(item)
    return courses

def most_courses(teacher_dict):
    teachers_list = {}
    for teacher in teacher_dict:
        teachers_list[teacher] = len(teacher_dict[teacher])
    return max(teachers_list, key=teachers_list.get)

def stats(teacher_dict):
      for teacher, courses in teacher_dict.items():
          number_of_courses = []
          for key in teacher_dict:
          teacher = ''
          num = 0
          for item in teacher_dict[key]:
              num += 1
          number_of_courses.append((key,num))
      return big_list.append([teacher, number_of_courses])

1 Answer

Chris Howell
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Chris Howell
Python Web Development Techdegree Graduate 49,702 Points
Chris Howell
.a{fill-rule:evenodd;}techdegree seal-36
Chris Howell
Python Web Development Techdegree Graduate 49,702 Points

Hi Maiia Spivak

I ran your code in my Python Shell, it seems you have some indentation errors.

Make sure you are using 4 spaces (not just 1 TAB) and if you use an advanced text editor or IDE, there is a way to make a TAB press equal to 4 character spaces instead of the actual whitespace character tab.

I fixed the indentation and your code is passing all but stats.

Maiia Spivak
Maiia Spivak
3,038 Points

Thank you Chris. I already fixed the spacing, and I am still struggling with the stats function. Could you have a look at it? What is wrong?

Maiia Spivak
Maiia Spivak
3,038 Points

Here is my another attempt:

def stats(teacher_dict): big_list = [] for teacher in teacher_dict.items(): number_of_courses = len(teacher_dict[teacher]) return big_list.append([teacher, number_of_courses])

Chris Howell
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Chris Howell
Python Web Development Techdegree Graduate 49,702 Points
Chris Howell
.a{fill-rule:evenodd;}techdegree seal-36
Chris Howell
Python Web Development Techdegree Graduate 49,702 Points

So the problems I see with the stats code, without giving any answer. Ill try to guide you to the answer

def stats(teacher_dict):
    # imagine that teacher_dict holds the data below...
    # teacher_dict = {'Kenneth Love': ['Python Basics', 'Python Collections']}

    big_list = []
    for teacher in teacher_dict.items(): # .items() is a tuple of (key, value)
        # teacher is holding: ('Kenneth Love', ['Python Basics', 'Python Collections'])

        number_of_courses = len(teacher_dict[teacher]) # This wont work, because of what teacher above is holding

        return big_list.append([teacher, number_of_courses]) # return here immediately stops your loop and returns item
Maiia Spivak
Maiia Spivak
3,038 Points

Thank you Chris! Will keep trying.