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# Stats Challenge (Step 3) - How can I improve my code?

This step really challenged me, but I powered through it with many tests in the python interpreter and my own code editor. My code passed the challenge but I feel like there might be an easier, more pythonic way of thinking about these things.

At first I ran into string conversion issues when trying to append stuff directly into my teachers list. But I eventually moved away from that and decided on using a sub-list and appending that to the main teachers list instead. This one really made me think hard about how I could create a list of lists.

How can I improve my code?

```def stats(teacher_dict):
teacher_list = []
for teacher in teacher_dict:
sub_list = ['', 0]

name = teacher
num_classes = len(teacher_dict[teacher])

sub_list[0] = name
sub_list[1] = num_classes
teacher_list.append(sub_list)
return teacher_list
```

MOD

You have all the right elements. The only improvements would be to streamline the statements.

```# The for loop block
sub_list = ['', 0]

name = teacher
num_classes = len(teacher_dict[teacher])

sub_list[0] = name
sub_list[1] = num_classes
teacher_list.append(sub_list)

# Can be replaced by
teacher_list.append([teacher, len(teacher_dict[teacher])])
```

Using the `dict.items()` method to return both the key and the value, this can be compress further:

```def stats(dct):
result = []
for teacher, course_list in dct.items():
result.append([teacher, len(course_list)])
return result
```
PLUS
```def stats(dict):
slist = []
for key, value in dict.items():
slist.append([key, len(value)])
return slist
```