most useful python modules

Modules and Packages (official website https://docs.python.org/3/contents.html) 1. Modules1.1 A. py file (usually defined as a function or data or method) can be called as a moduleThe 1.2 module can contain executable statements and definitions of functions that are intended to initialize modules that are executed only when the module name is first encountered importing import statements (the import stateme

Introduction to a Python modulePython module:A code-heavy program can be segmented into several pieces of code that are organized, independent but interacting with each other, and these self-contained, organized snippets of code are modulesThe module behaves as a code file that ends in. py in physical formA file is seen as a standalone module, and a module can be viewed as a fileThe file name of the module is the name of the module plus the extension.

The hashlib and base64 encryption modules in python use instances, and hashlibbase64 I have seen several bloggers learn python by breaking through each module. I also follow this example. This article describes the modules involved in python encryption. Hashlib The hashlib m

This entry collects common database interface modules in Python, including various mainstream relational databases and some common interfaces. Unless otherwise specified, all (or partially implemented) The DB-API standards. For more extensive Python database technology, see Python database development overview. 1. D

In order to write maintainable code, we grouped many functions into separate files so that each file contained relatively few code, and many programming languages used this way of organizing code. In Python, a. py file is called a module.Why use a module?Similar to the C language:1, greatly improve the maintainability of the Code;2, very versatile code can be reused, can be referenced by a third party;3, different

The Ython Pickle module acts as a persistent storage data.Often encountered in the Python program run to get some strings, lists, dictionaries and other data, want to save for a long time, easy to use later, rather than simply put in memory shutdown power loss data. The pickle module in the Python module is useful for converting objects into a format that can be

Python Common module Two ShelvePickleJson Shelve module The internal structure is actually the dictionary type, the storage time specifies the corresponding key, the content is stored as value, and takes out the value directly through key. Note that the file name does not require any suffixes because the system defaults to. db as the suffix name. Code 1 storing content import shelvedef fun1(): pass= shelve.open(‘

We saw the functions and objects before. In essence, they are all for the better organization of existing procedures to facilitate reuse. Modules (module) are also intended for the same purpose. In Python, a. py file forms a module. Through modules, you can invoke programs in other files. Introducing Modules We firs

of the PYTHONPATH environment variable Sys.modules.keys () to return the list of all modules that have been imported Sys.modules returns the module field of the system import, key is the module name, and value is the module sy S.exc_info () Gets the exception class currently being processed, Exc_type, Exc_value, exc_traceback the exception details currently handled Sys.exit (n) exit the program, exit normally (0 Sys.hexversion gets the version value

to implement There is no doubt that it is safer to fail the program accidentally because of some minor negligence. Try: Except this exception handling mechanism is to replace if that way, allowing your program to enhance robustness and fault tolerance without sacrificing readability Exception types are customized for each exception (Python unifies classes and types, type is a Class), and for the same exception, a except can be

In general, we will write our own Python module and Python's own modules stored separately to achieve easy maintenance purposes. The Python runtime environment is a sys.path list when looking for a module, and if we want to add a custom module to the runtime, there are three main ways to do this: 1. Add a new path to the Sys.path list (only works for the current

Modules (module)Python has a concept called module, which is similar to a header file in C and a package in Java, such as in Python to invoke the SQRT function, which must be introduced into the math module with the Import keyword. In layman's terms, a module is like a toolkit, and if you want to use the tool in the toolkit (like a function), you need to import t

mystuff[' Apple '] remember this concept of "get X from Y", now look at the module, you've created and used some of the modules, and you've seen some of their properties: 1. A module is a Python file that contains functions and variables. 2. You can import this file. 3. You can then use the '. ' operator to access the functions and variables in the module. If I had a module named mystuff.py and put a funct

Example of the usage of the time and datetime modules in Python, pythondatetime Time module method:Time. time (): Get the timestamp of the current time Time. localtime (): receives a timestamp and converts it to a tuples of the current time. If no parameter is specified, time. time () is input as the parameter by default. Time. localtime (): Index Attribute Descrip

After years of using Python, I stumbled upon features and features that we didn't know in the past. Some can be said to be very useful, but they are not fully utilized. With that in mind, I've edited some of the features of Python that you should know about. Functions with any number of parametersYou may already know that Py