Check if an element is not in a list in Python
In this tutorial, we will show you how to check if an element is not in a list in Python.
In Python, not inuse
The keyword in Python incan be used to check if an element exists in a set. If an element exists, then it returns True; otherwise, it returns False. For example:
x = 3 in [1, 2, 5]
y = 1 in [1, 2, 5]
print(x)
print(y)
Output:
False
True
If we need to check if an element is not in the list, we can use not inthe - keyword. - notis a logical operator that Trueconverts - to - Falseand vice versa. So if an element is not in the list, it will be returned True.
x = 3 not in [1, 2, 5]
print(x)
Output:
True
Use the list __contains__method to check if an element is not in the list
In Python, we have some magic functions associated with classes that are not meant to be called directly, although possible. One of these __contains__functions called can be used to check if an element exists in a list. For example:
x = [1, 2, 5].__contains__(1)
print(x)
x = [1, 2, 5].__contains__(3)
print(x)
Output:
True
False
While this approach works, it is not recommended because magic functions are not set up to be called directly.
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