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  1. Real Python
    https://realpython.com › ref › builtin-functions › id

    id () | Python’s Built-in Functions – Real Python

    What is a Python identifier?

    This identifier is a numeric value (more specifically an integer) that corresponds to the object's memory address within the Python interpreter at any given time. An ID is assigned to an object at the time of its creation and each object is assigned a unique ID for identification. Each time we run the program, a different ID will be assigned.

    tutorialspoint.com
    Python id () (With Examples) …

    Output Here, the id()method returns a unique integer number for every unique value it is used with. In the above example, we have used the id() method with variables a, b and cand got their corresponding ids. As you can se…

    Output Here, the id()method returns a unique integer number for every unique value it is used with. In the above example, we have used the id() method with variables a, b and cand got their corresponding ids. As you can see, the id() method returns the integer 140472391630016 for both a = 5 and 5. Since both values are the same, the id is also the ...

    Programiz

    The id()method takes a single parameter: 1. object - can be a class, variable, list, tuple, set, etc.

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    The id()method returns: 1. the identity of the object (which is a unique integer for a given object)

    Continue reading

    Output Here, we have used the id()method with the objects of classes. When we use the id() method with the dummyFood object, we get the result 139984002204864.

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    Output: In the above example, we have used the id() method with a set fruit. In this case, we get the unique number as the id for the set - 140533973276928.

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    id () function in Python - GeeksforGeeks

    In Python, id () function is a built-in function that returns the unique identifier of an object. The identifier is an integer, which represents the memory address of the object.

    GeeksForGeeks
    What is `id()` function used for in Python? - Stack Overflow

    In my case, I have found the id() function handy for creating opaque handles to return to C code when calling python from C. Doing that, you can easily use a dictionar…

    Stack Overflow
  1. 123

    The id() function in Python returns a unique and constant integer that identifies an object during its lifetime. In CPython, this value corresponds to the object’s memory address.

    Example:

    x = [1, 2, 3]
    y = x
    z = [1, 2, 3]

    print(id(x)) # Unique ID for x
    print(id(y)) # Same as x (points to same object)
    print(id(z)) # Different from x and y
    print(id(x) == id(y)) # True
    print(id(x) == id(z)) # False
    Copied!

    Output:

    140642115230496
    140642115230496
    140642115230800
    True
    False
    Copied!

    How it works

    • The id() function takes one object as an argument.

    • Returns an integer that is unique for the object during its lifetime.

    • Two variables referencing the same object will have the same id.

    • Once an object is destroyed (garbage collected), its id may be reused for new objects.

    Common Use Cases

    • Checking if two variables point to the same object

    a = "hello"
    b = "hello"
    print(id(a) == id(b)) # Often True due to string interning
    Copied!

    • Debugging reference issues

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  2. W3School
    https://www.w3schools.com › python › ref_func_id.asp

    Python id () Function - W3Schools

    The id() function returns a unique id for the specified object. All objects in Python has its own unique id. The id is assigned to the object when it is created.

    Syntax

    id(object)
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  4. GeeksForGeeks
    https://www.geeksforgeeks.org › python › id-functio…

    id () function in Python - GeeksforGeeks

    Nov 29, 2023 · In Python, id () function is a built-in function that returns the unique identifier of an object. The identifier is an integer, which represents …

  5. Stack Overflow
    https://stackoverflow.com › questions

    What is `id()` function used for in Python? - Stack Overflow

    In my case, I have found the id() function handy for creating opaque handles to return to C code when calling python from C. Doing that, you can easily use a dictionary to look up the object …

    • Reviews: 4
    • ZetCode
      https://zetcode.com › python › id-builtin

      Python id Function - Complete Guide - ZetCode

      Apr 11, 2025 · This comprehensive guide explores Python's id function, which returns the identity of an object. We'll cover object identity, memory addresses, and practical examples of object …

    • pythonhelper.com
      https://pythonhelper.com › python › python-id-function

      Python id () Function - Identification in Python

      Learn how to use the built-in id() function in Python to get the unique identifier or memory address of any object. See examples of how to compare objects based on their ids and how to use id() …

    • TutorialsPoint
      https://www.tutorialspoint.com › python › python_id_function.htm

      Python id () Function - Online Tutorials Library

      The Python id () function is used to obtain the unique identifier for an object. This identifier is a numeric value (more specifically an integer) that corresponds to the object's memory address …

    • Includehelp.com
      https://www.includehelp.com › python › id-function-with-example.aspx

      Python id () Function: Use, Syntax, and Examples

      Dec 7, 2024 · Python id () function: In this tutorial, we will learn about the id () function in Python with its use, syntax, parameters, returns type, and examples.

    • Python Tutorial
      https://www.pythontutorial.net › python-built-in-fu…

      Python id (): Return the Identity of an Object

      Learn how to use the id() function to return an integer that identifies an object in Python. See examples of how to use id() with numbers, strings, …