Any Python file (ending .py) can be imported from another Python script. A single Python file is also called a module.
To import from a module, its name (without .py) needs to be given in the import statement. Import statements can look like this:
import fruit
import fruit as f
from fruit import fruit_prices
from my_package.fruit import fruit_prices
It is strongly recommended to list the imported variables and functions explicitly instead of using the import * syntax. This makes debugging a lot easier.
When importing, Python generates intermediate code files (in the pycache directory) that help to execute programs faster. They are managed automatically, and dont need to be updated.