You can type a list as of Python 3.5
https://docs.python.org/3/library/typing.html
from typing import List
vector: List[float] = list()
or
from typing import List
vector: List[float] = []
Python is dynamically typed however https://www.python.org/dev/peps/pep-0484/
Typing makes it easier to read code, easier understand it, make efficient use of your IDE tooling and create higher quality software. I guess that's why it's in the PEP.
Answer from Shaun Ryan on Stack Overflow Top answer 1 of 7
86
You can type a list as of Python 3.5
https://docs.python.org/3/library/typing.html
from typing import List
vector: List[float] = list()
or
from typing import List
vector: List[float] = []
Python is dynamically typed however https://www.python.org/dev/peps/pep-0484/
Typing makes it easier to read code, easier understand it, make efficient use of your IDE tooling and create higher quality software. I guess that's why it's in the PEP.
2 of 7
8
Like Dominus said,
from typing import List is deprecated since Python 3.9.
You don't need to import anything, you can just use list.
Example:
my_list: list[float] = list()
W3Schools
w3schools.com › python › python_lists.asp
Python Lists
Lists are used to store multiple items in a single variable. Lists are one of 4 built-in data types in Python used to store collections of data, the other 3 are Tuple, Set, and Dictionary, all with different qualities and usage.
Type Hints, can you indicate various types inside a list?
You could use List[Union[str, int]] for a list that contains strings and ints, but that is not what you have here. This is actually a list of tuples, each of which has a str and an int. For that you can use List[Tuple[str, int]] which specifically says that each tuple contains two items, the first of which is a string and the second an int. Also note that on Python 3.9+ you should use the built-in types rather than the ones defined in typing, so list[tuple[str, int]]. And note again that in your example list_of_grades[0] isn't a string, it's a tuple of (string, int). More on reddit.com
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November 15, 2021Checking the type of a list
It’s because you’re comparing the type of the meta[0] element with the object ‘list’. Try renaming 'list' to 'mylist': mylist = [4,6,3] meta = [mylist] print(type(meta[0]) == list) More on reddit.com
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February 7, 2024Exploring Python's list Data Type With Examples: Creating ...
03:56
Python Types: List, Tuple, Set, Dictionary - YouTube
14:40
Lists in Python Explained Simply (Full Tutorial) - YouTube
Python Lists & Tuples for Beginners | Python tutorial - YouTube
Lists | Python Type Hints for Beginners - YouTube
Real Python
realpython.com › python-list
Python's list Data Type: A Deep Dive With Examples – Real Python
June 26, 2026 - List literals are probably the most popular way to create a list object in Python. These literals are fairly straightforward. They consist of a pair of square brackets enclosing a comma-separated series of objects. ... This syntax creates a list of n items by listing the items in an enclosing pair of square brackets. Note that you don’t have to declare the items’ type or the list’s size beforehand.
Python documentation
docs.python.org › 3 › library › typing.html
typing — Support for type hints
For most containers in Python, the typing system assumes that all elements in the container will be of the same type. For example: from collections.abc import Mapping # Type checker will infer that all elements in ``x`` are meant to be ints x: list[int] = [] # Type checker error: ``list`` only accepts a single type argument: y: list[int, str] = [1, 'foo'] # Type checker will infer that all keys in ``z`` are meant to be strings, # and that all values in ``z`` are meant to be either strings or ints z: Mapping[str, str | int] = {}
Real Python
realpython.com › ref › builtin-types › list
list | Python’s Built-in Data Types – Real Python
The built-in list data type is a versatile and widely-used data structure in Python that allows for the storage and manipulation of ordered, mutable sequences of elements.
Google
developers.google.com › google for education › python › python lists
Python Lists | Python Education | Google for Developers
Python's built-in list type is defined using square brackets [ ] and elements are accessed using zero-based indexing.
InfoWorld
infoworld.com › home › software development › programming languages › python
How to work with the Python list data type | InfoWorld
September 6, 2023 - Use Python lists to store data in one-dimensional rows, access them by indexes, and sort them any which way you like.
Python documentation
docs.python.org › 3 › tutorial › datastructures.html
5. Data Structures — Python 3.14.8 documentation
2 days ago - We saw that lists and strings have many common properties, such as indexing and slicing operations. They are two examples of sequence data types (see Sequence Types — list, tuple, range). Since Python is an evolving language, other sequence data types may be added.
GeeksforGeeks
geeksforgeeks.org › python › python-lists
Python Lists - GeeksforGeeks
Data Types · Interview Questions · Examples · Quizzes · DSA Python · Data Science · NumPy · Pandas · Practice · Django · Flask · Last Updated : 19 Sep, 2026 · List is a built-in data structure used to store an ordered collection of items.
Published: 2 weeks ago
Wamaithanyamu
wamaithanyamu.com › python-lists
Using Lists in python with type hints
December 31, 2022 - # Import the type hint module # Any means the List will take in any type of data type from typing import List, Any # Initialised using square brackets my_empty_list: List[Any] = [] print(my_empty_list) my_list_of_integers: List[int] = [1,2,3,4] print(my_list_of_integers) my_list_of_floats: List[float] = [1.2, 3.4, 5.6] print(my_list_of_floats) my_list_of_strings: List[str] =["this", "is" ,"a" ,"string"] print(my_list_of_strings) my_list_of_booleans: List[bool] =[True,False,False,True] print(my_list_of_booleans) my_mixed_list: List[Any] = [1, "Hello", False, 1.23] print(my_mixed_list)
Python
docs.python.org › 3 › c-api › list.html
List Objects — Python 3.14.8 documentation
This instance of PyTypeObject represents the Python list type.
Medium
medium.com › @datasciencejourney100_83560 › all-about-list-data-type-in-python-for-data-science-6070ecde2a36
All You Need to Know about List Data Type in Python for Data Science | by Rina Mondal | Medium
September 3, 2025 - Lists are versatile and can contain elements of different data types, including numbers, strings, and other lists. Lists are defined by enclosing elements in square brackets ([]) and separating them with commas. In this blog, I will describe everything about list in Python:
LabEx
labex.io › tutorials › python-how-to-check-list-type-in-python-419404
How to check list type in Python | LabEx
Python lists can contain elements of different types, making them extremely flexible for various programming scenarios.
Reddit
reddit.com › r/learnpython › type hints, can you indicate various types inside a list?
r/learnpython on Reddit: Type Hints, can you indicate various types inside a list?
November 15, 2021 -
If I have a list that I know will have a certain type of object in the first element and a different type in the second. For instance, if I have a function that combines two lists and returns a lists of lists like so:
names = ["Brad Pitt", "Leonardo DiCaprio", "Henry Cavill", "Hugo Weaving"]
grades = [85,32,95,90]
def combine_lists():
names_grades = []
for i in range(0,4):
names_grades.append(names[i],grades[i])
return names_grades
Is it possible to type hint the return type so that it reflects the types in the list, something like this:
def combine_lists() ->List(str,int):
The point of this is that later I would be aware of the type I'm accessing when I try to read a specific element of the list for example:
list_of_grades = combine_lists()x = list_of_grades[0] #I want to know this is a string
Top answer 1 of 2
2
You could use List[Union[str, int]] for a list that contains strings and ints, but that is not what you have here. This is actually a list of tuples, each of which has a str and an int. For that you can use List[Tuple[str, int]] which specifically says that each tuple contains two items, the first of which is a string and the second an int. Also note that on Python 3.9+ you should use the built-in types rather than the ones defined in typing, so list[tuple[str, int]]. And note again that in your example list_of_grades[0] isn't a string, it's a tuple of (string, int).
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2
It would be better to return a list of tuples. In such case you could easily annotate like this: List[Tuple[str, int]]
Tutorialspoint
tutorialspoint.com › python › python_lists.htm
Python - Lists
List is one of the built-in data types in Python. A Python list is a sequence of comma separated items, enclosed in square brackets [ ]. The items in a Python list need not be of the same data type.
FastAPI
fastapi.tiangolo.com › python-types
Python Types Intro - FastAPI
As the list is a type that contains some internal types, you put them in square brackets: Python 3.10+ def process_items(items: list[str]): for item in items: print(item) Note · Those internal types in the square brackets are called "type parameters". In this case, str is the type parameter passed to list.
Reddit
reddit.com › r/learnpython › checking the type of a list
r/learnpython on Reddit: Checking the type of a list
February 7, 2024 -
Can someone explain why (type(meta[0]) == list) is False here?
list = [4,6,3] meta = [list] print(type(meta[0]) == list)
This prints False even though meta[0] is clearly a list. ChatGPT thinks this code should print True so at least I'm not the only one who's confused.
Top answer 1 of 2
14
It’s because you’re comparing the type of the meta[0] element with the object ‘list’. Try renaming 'list' to 'mylist': mylist = [4,6,3] meta = [mylist] print(type(meta[0]) == list)
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Mdw73 is right. Your code is checking the type of the first element in your list, not the list itself. To elaborate: 'list' is already defined in the Python language as an object type. You should not use it as an object name. If you do that, you redefine the meaning of list. Try this to see what I mean: # This will show that list is an object type print('list: ', list, type(list)) # You can create an object of the list type a = list((1,2,3)) print('a: ', a, type(a)) # Now let us redefine list to a variable of type list instead list = list((1,2,3)) # The type of list will now have changed from 'type' to 'list' print('list: ', list, type(list)) # If we once again try to create a list by using the list keyword, we will fail b = list((1,2,3)) On top of that, you should really use the isinstance() function when checking the type of an object.
Codecademy
codecademy.com › learn › python-3-data-structures-and-loops › modules › learn-python3-lists › cheatsheet
Python Data Structures and Loops: Lists Cheatsheet | Codecademy
In Python, lists are a versatile data type that can contain multiple different data types within the same square brackets.
Beautiful Soup
tedboy.github.io › python_stdlib › generated › generated › types.ListType.html
types.ListType — Python Standard Library
types.ListType · View page source · types.ListType¶ ·
Untitled Publication
sahilsss.hashnode.dev › types-of-lists-in-python-overview
Types of Lists in Python Overview - Sahil Saini's Blog
September 30, 2023 - Lists are created by placing a comma-separated sequence of items within square brackets []. Each item in a list can be of any data type, including integers, strings, floats, and even other lists.