`globals()`

The built-in globals() function returns a reference to the current global namespace dictionary, allowing you to access and manipulate the objects in the global scope:

>>> number = 42
>>> globals()
{
    '__name__': '__main__',
    '__doc__': None,
    ...,
    'number': 42
}

`globals()` Signature

globals()

Arguments

The built-in globals() function doesn’t take any arguments.

Return Value

Returns the dictionary implementing the current module namespace. This dictionary is the live namespace rather than a copy, so it always reflects the current state of the global scope, and writes to it create or rebind global names.

`globals()` Examples

With a variable defined in the global scope:

>>> greeting = "Hello, World!"
>>> globals()
{'__name__': '__main__', ..., 'greeting': 'Hello, World!'}

With a function defined in the global scope:

>>> def greet():
...     print("Hello")

>>> globals()
{'__name__': '__main__', ..., 'greet': <function greet at 0x...>}

`globals()` Common Use Cases

The most common use cases for the globals() function include:

Inspecting the current global namespace
Dynamically accessing and modifying global variables
Implementing dynamic function dispatch based on global names
Loading configuration parameters into the global scope

`globals()` Real-World Example

Say you have a JSON file containing configuration settings for an application:

{
    "DATABASE_URL": "postgres://user:pass@localhost/dbname",
    "DEBUG_MODE": true,
    "MAX_CONNECTIONS": 10
}

You can use globals() to load these settings into the global namespace:

import json

def load_config(config_file):
    with open(config_file) as file:
        config = json.load(file)
    globals().update(config)

# Usage
load_config("config.json")
print(DATABASE_URL)  # Output: postgres://user:pass@localhost/dbname

This example shows how globals() can be used to dynamically load configuration parameters, making them accessible as global variables in your application.

Inside a function, globals() always resolves to the namespace of the module where that function was defined, not where it’s called. If you move load_config() into a separate module and import it, then the settings land in that module’s namespace, and the importing module raises a NameError when it references DATABASE_URL.

Tutorial

Namespaces in Python

In this tutorial, you'll learn about Python namespaces, the structures that store and organize the symbolic names during the execution of a Python program. You'll learn when namespaces are created, how they're implemented, and how they support variable scope.

intermediate python

For additional information on related topics, take a look at the following resources: