Programmer's guide to python

1.11 Namespaces

>As seen in C++ namespaces are a collection of names of variables/functions, but unlike C++, Python does not have the namespace keyword and so no user defined namespaces. Python maintains all of the namespaces in a dictionary automatically. They are maintained/recorded according to the scope of a variable/function, just as in any other programming language.

Three types of namespaces.

>built-in: Are readily available functions without any import. They can be used anywhere inside a program.
>global: Are which user defines outside of any function/class. They can be used anywhere inside a program.
>local: Are which user defines inside a function/class. They cannot be used outside their class/function's scope.

## Built-in namespace
"""
# For example, some functions which do not require any import
print(), len(), map(), range(), list(), set(), str(), etc.
"""


## Global namespace
# importing any modules adds them global namespace
import time

# variables/functions/classes outside of any function/class
my_var = 10

def my_fun():
  pass


## Local namespace
def some_fun():
  # variables and functions defined here are in local namespace
  # these cannot be used/called outside 'some_fun()' scope
  my_var = 10

  def my_fun():
      pass