"from module import member" Statement

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∟"from module import member" Statement

This section provides a quick introduction of 'from module import member' statement, which imports a specific member of a given module.

What Is "from module import member" Statement? A "from module import member" statement is a variation of the "import" statement that imports a specific member of a given module. It uses these these syntax:

from module_name import member_name
from module_name import member_name as variable_name

When a "from module_name import member_name" statement is executed, Python system will do the following:

Search for the module file, module_name.py, in locations given in sys.path.
Load the module file in memory.
Execute sub-statements stored in the module file. This may define variables (attributes), functions and classes in the module.
Create a "module" object to store module's attributes, functions and classes defined during the execution.
Declare a variable with the given variable_name or member_name.
Assign the specified member object to the variable.

The following code shows you how to import a specific member defined in the module file.

# import class "first" from "module_test.py" as a local variable "f"
>>> from module_test import first as f
Hi there! - from 'module_test' module
Welcome on board! - from 'first' class

>>> type(f)
<class 'type'>

>>> o = f()

>>> o.rise()
count = 1 - from 'rise()' method

>>> o.rise()
count = 2 - from 'rise()' method

Note that a "from module_name import member_name" statement actually loads the entire module file into memory cache. But it gives you no access to the module.