How To Print A Variable’s Name In Python

In Python, printing a variable’s name can be a useful debugging technique or a way to enhance code readability. While the language itself does not provide a built-in method to directly obtain a variable’s name, there are several creative ways to achieve this. In this article, we’ll explore five simple methods to print a variable’s name in Python.

Print A Variable Name In Python

Below are the example of How To Print A Variable’s Name In Python.

• Using locals() Function
• Using globals() Function
• Using a Custom Function
• Using inspect module

Print A Variable’s Name Using locals() Function

In this example, the below code defines a function `print_variable` that takes a variable as an argument, finds its name within the local scope using list comprehension with `locals()`, and prints the variable name.

Python3

def print_variable(variable):
    variable_name = [name for name, value in locals().items() if value is variable][0]
    print(f"Variable name using locals(): {variable_name}")

# Example usage:
my_variable = 42
print_variable(my_variable)

Output

Variable name using locals(): variable

Print A Variable’s Name Using globals() Function

In this example, below code defines a function print_variable that takes a variable as an argument, finds its name within the global scope using list comprehension with globals(), and prints the variable name.

Python3

def print_variable(variable):
    variable_name = [name for name, value in globals().items() if value is variable][0]
    print(f"Variable name using globals(): {variable_name}")

# Example usage:
global_variable = "Hello, World!"
print_variable(global_variable)

Output

Variable name using globals(): global_variable

Print A Variable’s Name Using a Custom Function

In this example, below code defines a function get_variable_name that takes an object and a namespace as arguments, finds the object’s name within the given namespace using list comprehension, and returns the variable name.

Python3

def get_variable_name(obj, namespace):
    return [name for name, value in namespace.items() if value is obj][0]

# Example usage:
custom_variable = [1, 2, 3]
custom_variable_name = get_variable_name(custom_variable, locals())
print(f"Variable name using custom function: {custom_variable_name}")

Output

Variable name using custom function: custom_variable

Print A Variable’s Name Using inspect Module

In this example, below code uses the inspect module to define a function `get_var_name` that takes a variable as an argument and prints its name by inspecting the local variables in the current frame. It then calls this function with a variable named `variable` having a value of 42. Note: Using `==` for value comparison might be more appropriate in this context instead of `is`.

Python3

import inspect

def get_var_name(var):
    current_frame = inspect.currentframe()
    try:
        frame_locals = current_frame.f_back.f_locals
        var_name = [name for name, value in frame_locals.items() if value is var][0]
        print(f"Variable name: {var_name}")
    finally:
        del current_frame

variable = 42
get_var_name(variable)

Output

Variable name: variable