In Python, “dunder” methods, short for “double underscore” methods, are special methods that allow developers to define the behavior of built-in operations for custom objects. For instance, when you use the +
operator to add two objects, Python internally calls the __add__
method. Similarly, other operators have their corresponding dunder methods.
However, the term “not and
” operator might be a bit misleading, as there isn’t a direct “not and
” operator in Python.
Instead, Python provides individual operators for not
, and and
. But if we delve into the realm of bitwise operations, we find operators that might resemble this behavior: the bitwise NOT (~
) and the bitwise AND (&
).
Let’s explore the dunder methods associated with these operators.
Bitwise NOT (~) and its Dunder Method __invert__
The bitwise NOT operator flips the bits of a number. For a custom class, if you want to define or override the behavior of the ~
operator, you’d use the __invert__
method.
class BitwiseNumber: def __init__(self, value): self.value = value def __invert__(self): return BitwiseNumber(~self.value) def __repr__(self): return str(self.value) number = BitwiseNumber(5) print(~number) # Outputs: -6
In the above example, the __invert__
method returns a new BitwiseNumber
object with its value inverted.
Bitwise AND (&) and its Dunder Method __and__
The bitwise AND operator performs a bitwise AND operation between two numbers. For custom classes, the behavior of the &
operator can be defined or overridden using the __and__
method.
class BitwiseNumber: def __init__(self, value): self.value = value def __and__(self, other): if isinstance(other, BitwiseNumber): return BitwiseNumber(self.value & other.value) return NotImplemented def __repr__(self): return str(self.value) number1 = BitwiseNumber(5) # Binary: 101 number2 = BitwiseNumber(3) # Binary: 011 print(number1 & number2) # Outputs: 1 (Binary: 001)
In this example, the __and__
method checks if the other object is an instance of BitwiseNumber
and then performs a bitwise AND operation.
TLDR
While there isn’t a direct “not and” operator in Python, leveraging the __invert__
and __and__
methods, you can define how the bitwise NOT and AND operations work for custom objects, respectively.