Python The _ Operator

The _ operator in Python can have different meanings depending on the context. Here are some common uses of the _ operator:

In the interactive interpreter, _ represents the result of the last expression evaluated. For example, if you type 2 + 3 and press enter, you will see 5 as the output. Then, if you type _ * 2 and press enter, you will see 10 as the output, because _ holds the value of 5.

In a loop or a list comprehension, _ is often used as a placeholder for a variable that is not needed or used. For example, if you want to create a list of ten zeros, you can write [0 for _ in range(10)].

In internationalization (i18n) and localization (l10n) modules such as gettext, _ is used as an alias for a function that translates a string into another language. For example, if you write print(_(“Hello”)) and have a translation file that maps “Hello” to “Hola”, you will see “Hola” as the output.

In some naming conventions, such as PEP 8 style guide for Python code, _ is used as a prefix for private variables or methods that are not meant to be accessed from outside the class. For example, if you have a class Foo with a method _bar(), you should not call foo._bar() from another module.

Single underscore _ is a valid character in python. It can be used as a variable name. It is a special character that is used to store the result of the previous evaluation according to python docs.

# As a Variable
_ = 10
b = 20
sum = _+b
print(sum)
# output 30

# Restoring The Previous Evaluation Result
>>> 200+400
600
>>> _*5
# output 3000

If you have any questions about this code, you can drop a line in comment.

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