Python Modules

• Modules are way to structure python program. 
• A module would have set of related functionalities. 
• Each python program file (.py file) is a module, which imports other modules (object) to use names (attributes) they define using object.attribute notation. 
• All the top level names of a module are attributes, exported for use by the importer of this module.
• Filename of a module turns out to be an object name where it is imported.
• import re;  statement imports all the names defined in module re.from statements can be used to import specific names from a module. 
• Both the above statements finds, compiles and loads (if not yet loaded) the module. 
• Python by default imports modules only once per file per process, when the very first import statement is encountered. 
• With from statement, names can be directly used. module name is not required.