Learning python - module

• # What is a module?
  • A collection of already written functions #
  • # Others written functions, variables, methods, in a file (the file that we can be used directly)
  • # import os,re,sys,time
• # How to write a module
  • # When creating .py file, give him a name in line with the variable name naming the file name, the name is the module name
• Import Module #
  • # import time
  • # How to use time module name
    • # time.time()
  • # Import namespace
    • #import modules and the current file in a different namespace
  • # Module may be repeated if introduced
    • # Can not
  • # Determine how this module has been imported over
    • # print(sys.modules)
  • What # when you import the module happened?
    • # Find this module
    • # Determine whether the module is imported before, if not to import it belongs to create a namespace of this module, so the module name to point to this space
    • # Execution module
    • # Aliases to the module, since the module can only use this alias after using the alias reference variables
  • # import time as t,re as r
    • Introducing a plurality of modules #
    • # Specification recommends introducing order: introduction built, and then introduced into the expansion module, and finally introduced into the custom module
  • # from time import gmtime
    • # How to use from import
    • # Need to use a file from which the name, put the name came Import
    • #From import process in the implementation of this document will still be imported
    • # Import will come only with who
    • Namespaces and modules of the current file #
    • #From import process the import of what happened
      • # 1. Find module
      • # 2. Determines whether introduced through
      • # 3. If you had not been imported
        • # Create a namespace belong to this module
          • # This file is executed
        • # To the variable you want to import
        • # Variables you want to import to create a reference to the variables you want to import
    • # Import multiple names
      • #from time import time as t,gmtime as g
    • #from time import *
      • # Import time in more than a content module
    • Relations #from time import * and the __all__
      • * #__all__ constraint variables introduced in the module,
• Cycle # 1. Module reference ***
  • It does not allow circular references between modules #
• # 2. The module is loaded with modifications **
  • # Has been imported modules have changes, it will not be perceived
  • # So, we need to modify the module is running a program perceived, can only restart the program
• # 3. ***** use the module as a script
  • #if __name__ == '__main__':
    • # Code (written in this code inside the file as a script execution only when will be executed)
  • # Execute a file of way
    • # Cmd, pycharm execution: Direct executable file - way to script execution
    • # Import the file
    • Py files are #
      • # Direct run this file, this file is the script
      • # Import the file, this file is the module,
  • # When a file py
    • # As a script when: the ability to provide a separate function, to complete the self-interaction
    • # As a module of the time: the importer can be called this function, not self-interaction
  • # A file variable __name__
    • # When this file as a script execution __name__ == '__ main__'
    • # When this file as imported modules __name__ == 'module name'
• # 4. Module search path
  • # And the file is executed as a script with the module directory can be imported directly into
  • # In addition to the module under other paths again when the need to import a list of their own change sys.path