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Python Iterable

I have a question that goes "Make a function named first_4 that accepts an iterable as an argument and returns the first 4 items in the iterable." and am stuck on what to do. How do I make the iterable?

4 Answers

you can try this

def man(iterable): return iterable[:4]

this will take an argument which is iterable and return the first four values of that iterable

Thank worked, thank you!

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

In iterable is anything that can be iterated upon. Such as a list, str, tuple. See docs: iterable

If you just want the first for items you can use the indexing [:4], such as:

In [8]: tup = (1, 2, 3, 4, 5, 6)

In [9]: tup[:4]
Out[9]: (1, 2, 3, 4)

If you want to use a function:

In [10]: def first_4(iterable):
   ....:     return iterable[:4]

In [11]: first_4(tup)
Out[11]: (1, 2, 3, 4)

You could also create a for-loop and inspect each item if you need operate on each item individually:

In [15]: def first_4(iterable):
    for item in range(4):
        # operate on item

In [16]: first_4(tup)

Hi Larissa,

That's describing what kind of data will be passed to your function. So, your function will receive an iterable object, which means you can put it in a loop and look at each element.

my_list = [1, 2, 3]  # this is an iterable

# function with a silly name that accepts one argument - which I am choosing to call itr, for iterable
def foo(itr):
  for element in itr:
    # lets see what's inside itr!

Hope this helps!


This is what I entered, but it isn't working: first_4 = (1, 2, 3, 4, 5)

first_4 [:4]

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

There should not be a space in between: first_4[:4], but the interpreter is flexible:

first_4 = (1,2,3,4,5)

In [18]: first_4 [:4]
Out[18]: (1, 2, 3, 4)

In [19]: first_4[:4]
Out[19]: (1, 2, 3, 4)

It still says it's incorrect, but it just says try again, so I don't know how I should change it

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Can you post what you have entered and the error message given back. Sometimes it's the line above that causes the error.