Python

List Format: name = [] name = [Name1, name2, Name3, Name4, Name5] #针对列表的操作 Name.index ("name1") #查询指定数值的下标值Name.count ("name1") #查询指定数值的总数Name.clear ("name") #清空列表Name.reverse ("name") #反转列表数值Name.sort ("name") #排序, precedence special characters-

In order to climb the model's picture, we first need to find each model's own page. By looking at the source of the page, we can find that the characteristics of the model's respective pages are as follows: We can get the page addresses of each

Crawl QQ space and so on most of the pages need to login, research QQ login rules, have to analyze a large number of JavaScript encryption decryption, this can definitely drop a few pounds of hair. And now with the Selenium tool, MA Ma no longer

Polymorphism is a basic feature of object-oriented language, and polymorphism means that variables do not know what the referenced object is, and behave differently depending on the object of reference. When dealing with polymorphic objects, you

Lxml is the most powerful and Easy-to-use library in the Python language and XML and HTML work. lxml is a python binding for the LIBXML2 and LIBXSLT libraries. What distinguishes it is that it takes into account the speed and functional integrity of

Numeric type: integer (int), long Integer (length), floating-point number (float), plural (complex), no need to specify numeric types when defining variables, such as: A=1, a=12.5 Operators: In addition to subtraction and powers * *, Division/,

A python conditional statement is the execution result (true or false) of one or more statements that determines which block of code is executed The Python program language specifies that any non-0 and non-null (NULL) values are true,0 or null to

The collection in Python has two main functions, one is to establish a relationship, the other is to eliminate duplicate elements The format of the collection is set (element) Take a concrete look at the following actions. >>> e = set

To get time related information, to use the Python timer module, there are many very useful features in the Python time module, you can go to the official document to understand the current time, to get the time stamp of the current time, the

The Easy_install command may be used in Python when you need to install a Third-party python package. Easy_install is a command from the Setuptools package developed by Peak (Python Enterprise application kit), so use Easy_ Install is actually

Algorithm principle Algorithm One 1) will be long Web site MD5 generated 32-bit signature string, divided into 4 paragraphs, 8 bytes per paragraph;2 to the four-segment loop, take 8 bytes, consider him as 16-string and 0X3FFFFFFF (30-bit 1) and

Python basicsA string is any text enclosed by single quotation marks or double quotation marks, such as 'ABC' and "xyz.If 'is also a character, it can be enclosed by "". For example, "I'm OK" contains the characters I,', m, space, O, k, Six

0X00 list and metadataIn Python, there is something called sequence, which can be imagined as a pile of data. Data structures such as arrays, linked lists, stacks, and queues can be implemented through sequences.There are several sequences. Common

Python iteratorThe iterator is an object that implements the iterator protocol. In Python, the iterator Protocol means that objects with the next method will move forward to the next result. At the end of a series of results, the StopIteration is