PRint related
print can print multiple expressions, just separate them with commas. A space will be inserted between each parameter in the result. Use + to avoid spaces, such as
>>> print 'age:',42
age: 42
>>> print 'hello'+','+'world'
hello,world
Add a comma at the end of the print statement, and the following statements will Print on the same line as the previous statement, such as
print 'hello', print 'world'
result
>>>
hello world
import related
from sometmodule import somefunc,anotherfunc,yetanotherfunc
from somemodule import * -- Import all functions in the module
import somemoudle as othermodulename -- Give the module an alias
form somemodule import somefunc ad otherfuncname -- Give the imported function an alias
Assignment related
Sequence unpacking or optional unpacking - unpack the sequence of multiple values and put it into the sequence of variables, such as
>>> scoundrel = {'name':'Robin','firlfriend ':'marion'}
>>> key, value = scoundrel.popitem()
>>> key
'firlfriend'
>>> value
'marion'
chain Assignment--a shortcut for assigning the same value to multiple variables, such as
x=y=somefunction()
Incremental assignment--place the expression operator to the left of the assignment operator =, such as
x += 1
Statement block
The colon (:) is used to identify the beginning of the statement block. Each statement in the block is indented (the indentation amount is the same). When the indentation is the same as that of the closed block, it means that the current block has ended.
Threesome
pass -- You don’t have to do anything with the program.
del -- deletes the object but does not affect the value, such as
>>> x = y = [1,2]
>>> y[1] = 'p'
> >> y
[1, 'p']
>>> (most recent call last):
File "
NameError: name 'x' is not defined
>>> y
exec -- Execute a string statement
>>> exec("print 'hello, world!'")
hello, world!
60

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In Python, you can use for loops, enumerate and list comprehensions to traverse lists; in Java, you can use traditional for loops and enhanced for loops to traverse arrays. 1. Python list traversal methods include: for loop, enumerate and list comprehension. 2. Java array traversal methods include: traditional for loop and enhanced for loop.

The article discusses Python's new "match" statement introduced in version 3.10, which serves as an equivalent to switch statements in other languages. It enhances code readability and offers performance benefits over traditional if-elif-el

Exception Groups in Python 3.11 allow handling multiple exceptions simultaneously, improving error management in concurrent scenarios and complex operations.

Function annotations in Python add metadata to functions for type checking, documentation, and IDE support. They enhance code readability, maintenance, and are crucial in API development, data science, and library creation.


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