[Introduction to Udemy Python 3 + Application] 38. When judging None

** * This article is from Udemy "[Introduction to Python3 taught by active Silicon Valley engineers + application + American Silicon Valley style code style](https://www.udemy.com/course/python-beginner/" Introduction to Python3 taught by active Silicon Valley engineers + application + American Silicon Valley style code style ")" It is a class notebook for myself after taking the course of. It is open to the public with permission from the instructor Jun Sakai. ** **

■ When judging None

◆None In Python, an empty object is referred to as None.

◆ Judgment of None

None


is_empty = None

if is_empty == None:
    print('None!!!')

result


None!!!

Of course, you can use == to make a judgment as you have done so far, It is rare to use == in the judgment of None.

◆ Judgment by is

None_is


is_empty = None

if is_empty is None:
    print('None!!!')

result


None!!!

Keep in mind that ʻis` is often used to determine None.

◆ Difference between == and ʻis`

=_is


print(1 == True)
print(1 is True)

result


True
False

The exact difference doesn't have to be known at this stage, ʻIs is True when the left and right sides are exactly the same. Remember to use ʻis because it is most often judged as None.

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