Python dataclass copy

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Python `dataclass.copy()` Method

The `copy()` method is available for data classes in Python. It is used to create a shallow copy of the data class object. A shallow copy means that the copying process creates a new data class object but does not clone the contents of the object i.e., it creates a new object with references to the original object’s attributes.

Here is an example to demonstrate the usage of `copy()` method:

    
      import dataclasses
      
      @dataclasses.dataclass
      class Person:
          name: str
          age: int
      
      # Create a Person object
      john = Person("John", 25)
      
      # Create a shallow copy of the object
      john_copy = john.copy()
      
      # Verify the contents of the original and copied objects
      print(john.name, john.age)  # Output: John 25
      print(john_copy.name, john_copy.age)  # Output: John 25
      
      # Modify the copied object
      john_copy.name = "John Doe"
      john_copy.age = 30
      
      # Verify the modifications
      print(john.name, john.age)  # Output: John 25
      print(john_copy.name, john_copy.age)  # Output: John Doe 30

In the above example, we define a `Person` data class with attributes `name` and `age`. We create a `john` object of the `Person` class and then use the `copy()` method to create a shallow copy of the `john` object, which is assigned to `john_copy`. Both the original and copied objects have the same values for their attributes.

Later, we modify the `name` and `age` attributes of the copied object (`john_copy`) and observe that the modifications do not affect the original object (`john`). This behavior is because the shallow copy creates a new object with references to the original object’s attributes, so any changes made to the attributes of the copied object will not reflect in the original object.

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