I've struggled on this problem for a while

Question

It keeps saying Val not defined or something, I've reviewed the videos a couple times and still couldn't think of anything or maybe there's something I'm not completely understanding.
iterating_ranges.py
my_list = []
for i in my_list.append(val):
    print(i)

Peter Vann · Answer

Hi Jorge!
This passes:
python
my_list = []
for i in range(10):
    my_list.append(i)

range(10) creates your 0-9 set of values that the loop iterates over where each i is that iteration's value (0. 1, 2, 3, 4, etc., up to 9.)
By the way, range(10) goes 0-9
To go 0-10, you'd need range(11)
mylist.append(i) appends the value if each iteration's i variable to the mylist list
The range function is a very cool feature of python (shorthand code) that makes it easy to do that type of loop iteration.
Otherwise, you'd have to do something like:
```python
mylist = []
myrange = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
for i in myrange:
     mylist.append(i)
```
Which would be kinda stupid (in this exact scenario), actually, because the end result would leave you with mylist and myrange being identical lists!?! LOL
More info:
https://www.w3schools.com/python/reffuncrange.asp
I hope that helps.
Stay safe and happy coding!
Bonus:
if you ran this:
```python
my_list = []
for i in range(10):
     mylist.append(i)
     print(mylist)

or this:
python
mylist = []
myrange = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
for i in myrange:
     mylist.append(i)
     print(my_list)

your output would be the same:

[0]
[0, 1]
[0, 1, 2]
[0, 1, 2, 3]
[0, 1, 2, 3, 4]
[0, 1, 2, 3, 4, 5]
[0, 1, 2, 3, 4, 5, 6]
[0, 1, 2, 3, 4, 5, 6, 7]
[0, 1, 2, 3, 4, 5, 6, 7, 8]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
```

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Jorge Grajeda

Jorge Grajeda

I've struggled on this problem for a while

1 Answer

Peter Vann

Peter Vann