<|im_start|>system
You are a helpful AI assistant.<|im_end|>
<|im_start|>user
consider this code:

somelist = []

for x in something:
    element = dosomething(x)

if "element" retuns a list, how do I append the list to somelist in a way that does not create a list of lists?

like for example, if somelist = ['banana'] and element = ['apple','orange'], how do I make a list of ['banana','apple','orange'] ?<|im_end|>
<|im_start|>assistant
You can use the `extend()` function of a list in Python. `extend()` adds elements from another list (or any iterable) to the end of the current list.

Here's how you can use `extend()` in your code:

```python
somelist = ['banana']

for x in something:
    element = dosomething(x)
    if isinstance(element, list):   # check if 'element' is a list
        somelist.extend(element)
```

In this modified version of your code, `somelist.extend(element)` will add each item in `element` to `somelist`. If `element` is ['apple', 'orange'], `somelist` will become ['banana', 'apple', 'orange']. 

Note the use of `isinstance()` to check if `element` is a list. This is a safeguard in case `dosomething(x)` returns something other than a list. If `dosomething(x)` always returns a list, you can remove this check.<|im_end|>
<|im_start|>user
Thanks didn't know that extend was a Python function. How could I implement `extend` if I didn't want to use the function defined in Python's core library?<|im_end|>
<|im_start|>assistant
If you want to implement your own version of the extend functionality without relying on the extend() method from Python's core library, you can create a custom function that achieves the same result. Here's an example:
```python
def custom_extend(list1, list2):
    for item in list2:
        list1.append(item)

# Example usage:
somelist = ['banana']
element = ['apple', 'orange']
custom_extend(somelist, element)
print(somelist)  # Output: ['banana', 'apple', 'orange']
```

In the custom_extend() function, we iterate over each item in list2 and use the append() method to add it to list1. This achieves the same behavior as the extend() method, where the elements of list2 are added individually to list1.

By using this custom function, you can extend a list without relying on the built-in extend() method.<|im_end|>
<|im_start|>user
hmm, are there any other ways of merging the lists?<|im_end|>
<|im_start|>assistant
Yes, there is a more concise way of merging lists using the `+=` operator. The code below is equivalent to the code in my previous response.

```python
somelist = []
for x in something:
    somelist += dosomething(x)
```<|im_end|>