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How to check if a variable is None in Python?

To check if a variable is None in Python, you can use a simple equality comparison with the None keyword. Here's an example:

x = None
if x is None:
    print("x is None")
else:
    print("x is not None")

In the above example, the is keyword is used to check if the variable x is None. If the condition evaluates to True, it prints "x is None"; otherwise, it prints "x is not None".

Note that the comparison is done using the is keyword rather than the equality operator ==. This is because None is a singleton object in Python, and the is operator checks for object identity, while the == operator checks for equality of values. In the case of None, it is more appropriate to use is to explicitly check for the None object.

Additionally, you can also use the is not operator to check if a variable is not None. Here's an example:

x = "Hello"
if x is not None:
    print("x is not None")
else:
    print("x is None")

In this example, the condition x is not None is used to check if the variable x is not None. If the condition evaluates to True, it prints "x is not None"; otherwise, it prints "x is None".

By using these techniques, you can easily check if a variable is None in Python.

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