In this Answer, we will learn how to check if an object is of a certain data type in Python.
Just as in every programming language, an object is an instance of a class, while a class is simply a template for creating objects with similar methods and properties.
In simpler terms, If we are creating an object, we are simply creating an instance of a class. The object you created has its own set of attributes and methods that are used to communicate with it. For example, when we create an object (e.g. "hello" ), which is an instance of the class str, we can interact with this object by using some methods, such as upper(), lower(), strip(), join(), and many more.
Below is a table showing some of the most common classes in Python and examples of its instance or objects:
Class | Description | Example (objects) |
int | Integer values | 1, 2, 3 |
float | Floating-point values | 1.0, 2.5, 3.14159 |
str | String of characters | "hello", "world" |
list | Ordered sequence of objects that are mutable | [1, 2, 3], ["a", "b", "c"] |
tuple | Ordered sequence of objects that are not mutable | (1, 2, 3), ("a", "b", "c") |
dict | A dictionary: mapping of keys to values | {"a":1, "b"::2, "c":3} |
set | A set: unordered collections of unique objects | {"a", "b", "c"}, {1, 2, 3} |
bool | Boolean values | True, False |
NoneType | Null values | None |
Note: The table above shows only the built in classes in Python. We can also create our own class using the
classkeyword.
To check if an object is of a certain data type in Python, we use the type() function.
type(x)
Where x represents the object of which the data type is to be obtained.
In the code below, we will create some objects and check for the data type using the type() function:
# Basic data typesmy_int = 42my_float = 3.14159my_string = "Hello, World!"# Data structuresmy_list = [1, 2, 3]my_tuple = (4, 5, 6)my_dict = {"a": 1, "b": 2, "c": 3}# A functiondef my_function():pass# A classclass MyClass:passall_objects = [my_int,my_float,my_string,my_list,my_tuple,my_dict,my_function,MyClass ]for objects in all_objects:print(objects, f"-------is of data type {type(objects)}\n")
Lines 1–17: We create some object of different classes in Python.
Lines 19–26: We create a list all_objects to house all the objects we created.
Lines 28–29: We iterate over the list of all the objects we created and obtain their data types using the type() function.