Using Python Libraries - Revision Notes
CBSE Class 12 Computer Science (Python)
Using Python Libraries
Revision Notes
- Start here in points
- A library refers to a collection of mudules that together cater to specific type of needs or applications.
- A module is a separately saved unit whose functionality can be reused at will.
- A function is a named block of statements that can be invoked by its name.
- Python can have three types of functions: built-in functions, functions in modules and user-defined functions.
- A Python module can contain objects like docstrings, variables, constants, classes, objects, statements, functions.
- A Python module has the .py extension.
- The doctrings are useful for documentation purposes.
- A Python module can be imported in a program using import statement.
- There are two forms of import statements
- import <modulename> [as <aliasname>]
- from <module> import <object>
- The built-in functions of Python are always available; one needs not import any module for them.
- The random module of Python provides random-number-generation functionality.
- The urllib module lets you send and receive http requests and their results and web browser lets you open a webpage from within a Python program.
- In order to create own package, it should be created so that it has a folder having its name and it also has a special file_init_.py in it. After this, it must be attached to site-packages folder of current Python installation.
- A package installed or attached to site-packages folder of Python installation can easily be imported using import command.
- Avoid using the from <module>import * form of the import statement, it may lead to name clashes. If you use plain import <module>, no problems occur.
- Namespace is a named logical environment holding logical grouping of related objects within a namespace, its member object is referred without any prefix.
- Module is independent grouping of code and data (variables, definitions, statements and functions).
- Module can be re-used in other programs.
- The file __init__.py in a folder, indicates it is an importable package, without __init__.py, a folder is not considered a python package.