What are enclosing functions?

Question

According to the python tutorial, functions look for variable names in the symbol tables of enclosing functions before looking for global functions:

The

Answer 1

The reason you cannot call child_function by itself, is that it is defined inside the parent_function. All python variable declarations use block scope, and declaring a function is no different.

Consider the following example.

>>> def parent_function():
...    y=10
...    def child_function():
...        print y
...    child_function()

>>> print y
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'y' is not defined

The variable y is not accessible outside the parent_function. Why would you expect that child_function would be any different that y?