> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/python/cpython/llms.txt
> Use this file to discover all available pages before exploring further.

# List Objects

> Working with Python list type

## Overview

Lists are mutable sequences of Python objects with O(1) indexing and append.

## Creating Lists

```c theme={null}
PyObject* PyList_New(Py_ssize_t len)
```

Create new list with `len` items (initially NULL).

**Example:**

```c theme={null}
PyObject *list = PyList_New(3);
PyList_SetItem(list, 0, PyLong_FromLong(1));  // Steals ref
PyList_SetItem(list, 1, PyLong_FromLong(2));
PyList_SetItem(list, 2, PyLong_FromLong(3));
return list;
```

## Accessing Items

```c theme={null}
PyObject* PyList_GetItem(PyObject *list, Py_ssize_t index)  // Borrowed!
Py_ssize_t PyList_Size(PyObject *list)
```

<Warning>
  `PyList_GetItem` returns **borrowed reference** - don't Py\_DECREF!
</Warning>

## Modifying Lists

```c theme={null}
int PyList_SetItem(PyObject *list, Py_ssize_t index, PyObject *item)  // Steals!
int PyList_Append(PyObject *list, PyObject *item)  // Doesn't steal
int PyList_Insert(PyObject *list, Py_ssize_t index, PyObject *item)
```

## See Also

* [Object Protocol](/c-api/object)
* [Reference Counting](/c-api/refcounting)