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# can someone explain to me what did he do at 2:58 and all the things with step[0] step[1]

can someone explain to me what did he do at 2:58 and all the things with step[0] step[1]

Right, you know that `enumerate()` takes a list and returns an enumerate object containing tuples with the elements of that list numbered according to their indexes, i.e.:

```animals = ["bird", "turtle", "cat"]
new_animals_list = list( enumerate(animals) )
# new_animals_list = [ (0, "bird"), (1, "turtle"), (2, "cat") ]
```

When the teacher uses `enumerate()` in that loop, he `print`s each one of the function's return value separately. Just like I'll do with my `animals` list:

```for animal in enumerate(animals):
print("{}: {}".format(animal[0], animal[1]))
```

When the loop runs for the first time, `animal` will be the following tuple: `(0, "bird")`. Using index notation, I access the tuple's elements (`animal[0]` and `animal[1]`).

Finally, the `.format()` method takes what's inside the parenthesis and replace the curly brackets (`{}`) in the string. The first pair of curly brackets is replaced by `animal[0]`, that is `0`, while the second pair is replaced by `animal[1]`, that is `"bird"`.

The same happens to the tuples `(1, "turtle")` and `(2, "cat")`.

```# Which results in:
# 0: bird
# 1: turtle
# 2: cat
```

Hope that helps! (:

So because of enumerate, step[0] = the index and step[1] = the value of that index?

Because otherwise you would think that step[0] would call the value, with the index 0, and step[1] would call the value, with the index 1?

Wait I think I understand it now. By printing a list with enumerate, it creates tuples out of those list items. Those tuples consist of both the list item, and the index it had. The index is now also its own item in the tuple. That's why you can call it with step[0] because it have gotten its own index now.

Right?