How was 'course' defined as a key?

Question

Kenneth used...'for course in course_minutes:
                                          print(course)'
to get a key printed. How was course defined for the key? Are naming conventions for dictionaries always set up as "key_value = {}"?
Thanks!

Chris Freeman · Accepted Answer

The default way to iterate over a dict is by keys. The following two lines are functionally equivalent:
```python
for course in course_minutes:
for course in course_minutes.keys():
```
The other two ways to iterate over a dict:
```python
for course in course_minutes.values():   # loop over the dict values
for course, value in course_minutes.items():  # loop over the dict key and values as pairs
```

cyber voyager · Answer

Hello Evan, when you iterating something with a for loop it goes like this (for x in list:) x actually is something that we name it anyway we like, it represents the item that we are right now iterating through. 
For example
python
something = ["Hey", "Hello", "Bonjour"]
for x in something:
     print(x) #The first time through the loop x represents Hey
                  #the second time Hello and the third time Bonjour

As for how he got the key from the loop this is what happend:
He looped through the dictionary which gave him only the keys, so he wrote exactly what I wrote in the example but he added  x.value()
Soooo every time he was going to print x which is the item of the dictionary he adds the .value() which takes the x key and returns it's value :p simple right?
I hope you understood it, if I am wrong somewhere correct me I just finished the lesson.

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Evan Huddleson

Evan Huddleson

How was 'course' defined as a key?

2 Answers

Chris Freeman

Chris Freeman

cyber voyager

cyber voyager