Python learns the scope of 7--variables

1. Scope of variables
(1) Variables defined within a function include arguments, function only within the scope of the functions, and local variables are similar.
(2) Global variables, inside functions can be called outside the function, even if the variable is defined after the function.
Note: Local variables and global variables are defined in the same way as other languages.
If you modify a global variable within a function Zjh,python creates a name for the global variable within the function.
Substitution of local variables. Therefore, changes to global variables within a function do not affect global variables.
Note: How to make changes to global variables work inside a function.
This global variable is defined inside the function with the GLOBALS keyword.
Example: Before use:

　　　　

After use:
　　　　

Python learns the scope of 7--variables