How does namespace placement occur in Python?

Namespaces in Python are organized hierarchically and managed by the LEGB rule (Local, Enclosing, Global, Built-in).

1. Local (Локальное): The innermost namespace. Created when a function is called, containing names defined inside that function (variables, local functions). Exists only during function execution.

   def my_function():
       x = 10  # Local variable
       print(x)
   

2. Enclosing (Окружающее/Нелокальное): Created for nested functions. Contains names from the enclosing (parent) function, not local to the inner function. Uses the nonlocal keyword.

   def outer_function():
       y = 20
       def inner_function():
           nonlocal y # Access variable from enclosing scope
           print(y)
       inner_function()
   

3. Global (Глобальное): Namespace at the module level. Contains names defined in the module (functions, classes, variables). Accessible from anywhere in the module. Created upon module import.

   z = 30 # Global variable in module
   def another_function():
       global z # Access global variable
       print(z)
   

4. Built-in (Встроенное): The outermost namespace. Contains Python's built-in functions and exceptions (print, len, Exception, etc.). Accessible from anywhere.

Python searches for a name starting from the local namespace, then enclosing, then global, and finally built-in. If not found, a NameError is raised.

Namespaces are represented as dictionaries, with names as keys and objects as values.

print(locals())  # Local namespace of current function
print(globals()) # Global namespace of current module